The Big Bang Theory Episode Guide

Here is the episode guide for The Big Bang Theory. Each episode has the title, writer, director, and a description listed. The descriptions are sourced from locations such as Wikipedia and official press releases

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24 - The Convergence Convergence

Written By: Steven Molaro & Tara Hernandez & Adam Faberman Directed By: Mark Cendrowski
Rating: 3.4 Audience: 14.76
Chaos ensues when Leonard’s recently divorced parents, Alfred and Beverly, and Sheldon’s devoutly religious mother, come to town. Also, Wolowitz and Koothrappali think the government is out to get them when they are contacted about their guidance system

23 - The Line Substitution Solution

Written By: Steve Holland & Saladin K. Patterson & Tara Hernandez Directed By: Anthony Rich
Rating: 3.0 Audience: 13.22
Sheldon hires Stuart to spend the day with Amy when he’d rather go to a movie screening. Also, Leonard’s mother, Beverly, comes to town and Penny struggles to make a connection with her

22 - The Fermentation Bifurcation

Written By: Steven Molaro, Jim Reynolds, Anthony Del Broccolo Directed By: Nikki Lorre
Rating: 3.4 Audience: 14.13
The gang goes to a wine bar and runs into Penny’s old boyfriend, Zack (Brian Thomas Smith). Also, Bernadette gets stuck spending the evening with Sheldon when she can’t go wine tasting with the group, and things don’t go as planned when Koothrappali introduces his new girlfriend, Claire

21 - The Viewing Party Combustion

Written By: Eric Kaplan, Maria Ferrari and Jeremy Howe Directed By: Mark Cendrowski
Rating: 3.2 Audience: 14.16
Everyone must choose sides when a small argument between Leonard and Sheldon erupts into a heated fight during a group get-together

20 - The Big Bear Precipitation

Written By: Chuck Lorre, Dave Goetsch and Tara Hernandez Directed By: Mark Cendrowski
Rating: 3.1 Audience: 13.50
Sheldon spills a secret of Leonard’s when the two take a weekend cabin trip with Penny and Amy. Also, when Koothrappali goes overboard with pregnancy gifts, Wolowitz and Bernadette must draw the line

19 - The Solder Excursion Diversion

Written By: Bill Prady, Eric Kaplan, Maria Ferrari Directed By: Mark Cendrowski
Rating: 3.5 Audience: 14.24
Amy is shocked at a revelation from Sheldon after she buys him a new laptop. Also, Koothrappali sells out Leonard and Wolowitz after they lie to their wives in order to attend an early screening of a movie

18 - The Application Deterioration

Written By: Steven Molaro, Eric Kaplan and Adam Faberman Directed By: Mark Cendrowski
Rating: 3.5 Audience: 14.68
Leonard, Sheldon, and Wolowitz run into problems when they file for a patent for their infinite persistence gyroscope. Also, Penny, Amy and Bernadette give Koothrappali dating advice when Emily reaches out to him after their breakup

17 - The Celebration Experimentation

Written By: Chuck Lorre, Eric Kaplan, Jeremy Howe Directed By: Mark Cendrowski
Rating: 3.8 Audience: 15.94
After more than nine years together, the gang finally celebrates Sheldon’s birthday, surprising him with a special guest

16 - The Positive Negative Reaction

Written By: Eric Kaplan, Jim Reynolds, Saladin K. Patterson Directed By: Mark Cendrowski
Rating: 3.8 Audience: 15.24
When the gang finds out about Bernadette’s pregnancy, they celebrate by singing karaoke. Also, Bernadette is concerned when Wolowitz freaks out over her pregnancy announcement, and Wolowitz is convinced he must make more money to provide for the baby

15 - The Valentino Submergence

Written By: Steve Molaro, Jim Reynolds, Tara Hernandez Directed By: Mark Cendrowski
Rating: 3.8 Audience: 16.25
Sheldon and Amy host a live Valentine’s Day episode of Fun with Flags, Leonard and Penny grapple with getting older, Howard and Bernadette find a surprise in their hot tub and Raj is torn between Emily and the cute girl he met at the Comic Bookstore

14 - The Meemaw Materialization

Written By: Chuck Lorre, Jim Reynolds and Maria Ferrari Directed By: Mark Cendrowski
Rating: 3.8 Audience: 15.29
Sheldon’s thrilled when his Meemaw comes to visit, but his excitement quickly fades when she butts heads with Amy. Also, Raj meets a new girl at the comic book store who makes him question his relationship with Emily

13 - The Empathy Optimization

Written By: Chuck Lorre, Eric Kaplan, Dave Geotsch Directed By: Mark Cendrowski
Rating: 3.8 Audience: 15.75
After having to deal with a sick Sheldon, Leonard, Penny and the gang try to treat themselves to a Sheldon-free weekend

12 - The Sales Call Sublimation

Written By: Steve Holland, Jim Reynolds and Saladin K. Patterson Directed By: Mark Cendrowski
Rating: 3.8 Audience: 15.85
Penny gets more than she bargained for when Leonard agrees to meet with a psychiatrist on her behalf. Also, Sheldon and Koothrappali collaborate on an astronomical discovery, and Wolowitz and Bernadette can’t believe what they are feeling after Stuart moves out

11 - The Force Awakens

Written By: Steven Molaro Eric Kaplan and Tara Hernandez Directed By: Mark Cendrowski
Rating: 4.1 Audience: 17.23
After more than five years of dating, Sheldon and Amy spend their first night together. Also, Leonard, Wolowitz, and Koothrappali must decide who will take their extra Star Wars movie ticket

10 - The Earworm Reverberation

Written By: Eric Kaplan, Jim Reynolds, Saladin Patterson Directed By: Mark Cendrowski
Rating: 3.8 Audience: 15.27
Sheldon has a revelation when he realizes why a song was stuck in his head. Also, Amy invites Dave (Stephen Merchant) over for dinner despite their previously awkward date, and Wolowitz and Koothrappali become obsessed with a fan of their band

09 - The Platonic Permutation

Written By: Jim Reynolds, Jeremy Howe and Tara Hernandez Directed By: Mark Cendrowski
Rating: 3.8 Audience: 15.19
Sheldon and Amy try hanging out as friends when they spend Thanksgiving together at the aquarium. Also, Wolowitz reluctantly agrees to volunteer at the soup kitchen with Bernadette, Raj and Emily, and Penny discovers that Leonard knows more about her than she thought

08 - The Mystery Date Observation

Written By: Steven Molaro, Eric Kaplan and Jim Reynolds Directed By: Mark Cendrowski
Rating: 3.7 Audience: 14.92
Sheldon, Wolowitz and Koothrappali post an online advertisement to find Sheldon a new girlfriend. Also, when Amy is coy with details about a guy she is dating, Penny and Bernadette decide to spy

07 - The Helium Insufficiency

Written By: Chuck Lorre, Jim Reynolds and Tara Hernandez Directed By: Nikki Lorre
Rating: 3.7 Audience: 14.81
While being interviewed for a documentary about Spock from “Star Trek,” Sheldon struggles to suppress his emotions about his recent break-up with Amy. Also, Wolowitz and Bernadette butt heads over remodeling his childhood home

06 - The Spock Resonance

Written By: Steve Holland, Maria Ferrari and Anthony Del Broccolo Directed By: Mark Cendrowski
Rating: 4.4 Audience: 16.32
In the midst of a nation-wide helium shortage, Sheldon and Leonard take desperate measures to get the supplies they need. Also, Penny and Bernadette download a dating app on Amy's phone to try and find her a new man

05 - The Perspiration Implementation

Written By: Chuck Lorre, Eric Kaplan and Maria Ferrari Directed By: Mark Cendrowski
Rating: 3.9 Audience: 14.68
The guys take a fencing lesson from Barry Kripke and Sheldon finds himself in an awkward position when Kripke expresses interest in Amy. Also, when Stuart struggles to get female customers at the Comic Book Store, Penny, Amy and Bernadette come by to help him out

04 - The 2003 Approximation

Written By: Chuck Lorre, Steve Holland and Eric Kaplan Directed By: Mark Cendrowski
Rating: 3.9 Audience: 14.96
Sheldon learns of an impending change in his living arrangements and decides to revert back to 2003, a simpler time before he met Leonard and Penny. Also, Howard and Raj form a band to play at the Comic Book Store

03 - The Bachelor Party Corrosion

Written By: Dave Goetsch, Jim Reynolds, Jeremy Howe Directed By: Mark Cendrowski
Rating: 3.9 Audience: 15.40
The guys’ science skills are put to the test when they get a flat tire during Leonard’s bachelor party weekend in Mexico. Also, the girls force Penny to finally tell her family that she eloped with Leonard

02 - The Separation Oscillation

Written By: Steven Molaro, Steve Holland, Tara Hernandez Directed By: Mark Cendrowski
Rating: 3.8 Audience: 15.23
Leonard confronts the woman he kissed on the North Sea in an attempt to set Penny’s mind at ease. Also, Sheldon films a special episode of “Fun with Flags” after his breakup with Amy, and Bernadette feels guilty about withholding a secret from Penny

01 - The Matrimony Momentum

Written By: Chuck Lorre, Jim Reynolds, Maria Ferrari Directed By: Mark Cendrowski
Rating: 4.7 Audience: 18.20
After driving to Vegas to get married, Penny struggles with Leonard’s confession that he kissed another girl. Also, Sheldon doesn’t know how to act after Amy pushes pause on their relationship
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24 - The Commitment Determination

Story By: Chuck Lorre, Jim Reynolds, Maria Ferrari Directed By: Mark Cendrowski
Rating: 3.7 Audience: 14.64
Sheldon pushes Leonard and Penny to choose a date for their wedding and deals with dramatic changes in his own relationship with Amy

23 - The Maternal Combustion

Written By: Steven Molaro, Tara Hernandez, Jeremy Howe Directed By: Anthony Rich
Rating: 3.4 Audience: 13.85
Personalities collide when Sheldon and Leonard’s mothers finally meet. Meanwhile, Howard finally decides to “man up” and do his fair share of the housework – but not without a little help from his friends

22 - The Graduation Transmission

Written By: Chuck Lorre, Dave Goetsch and Anthony Del Broccolo  Directed By: Anthony Rich
Rating: 3.6 Audience: 14.63
Wolowitz questions his engineering abilities when he and Sheldon can’t get a toy drone to fly. Meanwhile, a cancelled flight nearly prevents Leonard from giving the commencement address at his former high school, and Raj pits his parents against each other when his father cuts him off financially

21 - The Communication Deterioration

Story By: Dave Goetsch, Steve Holland, Jeremy Howe Directed By: Mark Cendrowski
Rating: 3.9 Audience: 14.82
When Raj is asked to create a message in case a NASA mission discovers alien life, the guys fight over what he should do. Also, Penny is torn between auditioning for a movie or keeping her successful pharmaceutical sales job

20 - The Fortification Implementation

Written By: Jim Reynolds, Saladin Patterson, Tara Hernandez Directed By: Mark Cendrowski
Rating: 3.5 Audience: 14.78
When Sheldon and Amy build a blanket fort, they come to major crossroads in their relationship. Also, Wolowitz meets the half-brother he never knew he had, and when Penny is invited to appear on Wil Wheaton’s podcast, she and Leonard have a huge, on-air argument

19 - The Skywalker Incursion

Written By: Jim Reynolds, Tara Hernandez, Jeremy Howe Directed By: Mark Cendrowski
Rating: 3.4 Audience: 13.89
When Leonard and Sheldon are invited to speak at UC Berkeley, they take a detour to try to meet an idol. Also, when Bernadette and Howard battle over the fate of his Dr. Who TARDIS, Raj and Amy offer to settle the dispute with a game of ping pong

18 - The Leftover Thermalization

Written By: Steven Molaro, Maria Ferrari and Jeremy Howe  Directed By: Mark Cendrowski
Rating: 4.4 Audience: 16.13
Friction ensues when a magazine fails to mention Leonard in an article about the paper he co-wrote with Sheldon. Also, a blackout at Mrs. Wolowitz’s home leads to a final family dinner in her honor

17 - The Colonization Application

Story By: Dave Goetsch, Jim Reynolds and Tara Hernandez Directed By: Mark Cendrowski
Rating: 4.8 Audience: 18.17
Trouble arises when Amy learns Sheldon has applied for a one-way mission to colonize Mars. Also, a trip to the pet store ends in a fight for Sheldon and Amy, Leonard surprises Penny with a very “adult” purchase, and, Raj is caught snooping in Emily’s apartment

16 - The Intimacy Acceleration

Written By: Dave Goetsch, Eric Kaplan, Tara Hernandez Directed By: Mark Cendrowski
Rating: 4.5 Audience: 16.67
As a joke, Sheldon and Penny try an experiment designed to make participants fall in love. Also, Leonard, Amy, Raj and Emily spend the evening trying to escape a room with a “zombie.” And, after returning from Mrs. Wolowitz’ funeral, Bernadette and Howard run into trouble at the airport

15 - The Comic Book Store Regeneration

Story By: Jim Reynolds, Maria Ferrari and Jeremy Howe Directed By: Mark Cendrowski
Rating: 4.5 Audience: 17.49
Wolowitz receives some shocking news as everyone prepares for the reopening of Stuart’s comic book store. Penny teaches Sheldon how to “let it go,” but can’t follow her own advice after she learns something infuriating about Amy. Also, Leonard and Raj think they spot Nathan Fillion at a restaurant,

14 - The Troll Manifestation

Written By: Steven Molaro, Eric Kaplan and Tara Hernandez Directed By: Mark Cendrowski
Rating: 4.6 Audience: 17.09
After Leonard and Sheldon co-publish a physics paper, they must defend themselves against criticism from an online bully. Also, girls’ night finds Penny, Amy and Bernadette confronting embarrassing moments from their past

13 - The Anxiety Optimization

Written By: Eric Kaplan, Maria Ferrari and Adam Faberman Directed By: Mark Cendrowski
Rating: 4.5 Audience: 17.25
In the hopes of achieving a scientific breakthrough, Sheldon invites his friends to challenge him. Meanwhile, Wolowitz invents an embarrassing game about Raj

12 - The Space Probe Disintegration

Written By: Billy Prady, Eric Kaplan and Jim Reynolds  Directed By: Mark Cendrowski
Rating: 4.6 Audience: 18.11
Wolowitz tries to distract Raj, who is anxiously awaiting data from a space probe he helped launch. Meanwhile, Sheldon and Leonard go dress shopping with Penny and Amy

11 - The Clean Room Infiltration

Written By: Maria Ferrari, Tara Hernandez and Jeremy Howe  Directed By: Mark Cendrowski 
Rating: 3.9 Audience: 15.49
Leonard and Wolowitz nearly come to blows and turn to Raj for help in dealing with a work emergency. Meanwhile, Amy throws an authentic Victorian Christmas party, and Sheldon seeks revenge on her for making him celebrate the holidays

10 - The Champagne Reflection

Story By: Steven Molaro, Tara Hernandez and David Saltzberg, Ph.D Directed By: Mark Cendrowski 
Rating: 4.1 Audience: 14.61
Sheldon says a tearful goodbye to “Fun with Flags.” Also, Leonard, Howard and Raj look for something significant in a dead professor’s research, and Bernadette is shocked to learn her co-workers’ true feelings from Penny

09 - The Septum Deviation

Story By: Steven Molaro, Bill Prady and Maria Ferrari  Directed By: Anthony Rich 
Rating: 4.5 Audience: 16.90
When Leonard gets minor surgery on his nose, Sheldon is the one in need of sympathy. Meanwhile, Raj’s parents’ impending divorce causes Howard and Bernadette to work on their own marriage

08 - The Prom Equivalency

Story By: Jim Reynolds, Steve Holland, Jeremy Howe Directed By: Mark Cendrowski 
Rating:

4.3

Audience: 16.56
When the gang recreates a high school prom on the roof the of the guys’ apartment building, Sheldon feels pressure to participate in all the typical romantic traditions

07 - The Misinterpretation Agitation

Story By: Chuck Lorre, Eric Kaplan and Jim Reynolds Directed By: Mark Cendrowski 
Rating: 4.1 Audience: 16.25
The guys try to help Penny out of an awkward work dilemma. Meanwhile, Amy and Bernadette argue over whether or not female scientists should play up their sexuality

06 - The Expedition Approximation

Story By: Steven Molaro, Dave Goetsch, Tara Hernandez Directed By: Mark Cendrowski
Rating: 4.6 Audience: 16.02
Sheldon and Raj test whether they could survive a dark-matter research expedition in a salt mine by simulating the conditions in a steam tunnel. Meanwhile, Leonard and Penny seek advice from Wolowitz and Bernadette after they fight about money

05 - The Focus Attenuation

Story By: Jim Reynolds, Maria Ferrari, Adam Faberman Directed By: Mark Cendrowski
Rating: 4.5 Audience: 15.32
Amy and Bernadette accuse Penny of being a “buzzkill” after she gets an email from work during their Vegas weekend. Meanwhile, the guys try to invent something cool, but only come up with new ways to procrastinate

04 - The Hook-Up Reverberation

Story By: Steve Holland, Maria Ferrari and Tara Hernandez  Directed By: Mark Cendrowski
Rating: 4.5 Audience: 15.75
Raj’s honesty about his past comes back to haunt him after his girlfriend, Emily, is cold to Penny. Also, the guys consider becoming part-owners in Stuart’s comic book store

03 - The First Pitch Insufficiency

Story By: Chuck Lorre, Jim Reynolds and Anthony Del Broccolo  Directed By: Mark Cendrowski
Rating: 4.8 Audience: 16.38
Wolowitz is nervous after NASA asks him to throw out the first pitch at a Los Angeles Angels game. Meanwhile, Leonard and Penny try to prove Sheldon wrong after he says that he and Amy are a “superior couple"

02 - The Junior Professor Solution

Story By: Steven Molaro, Eric Kaplan and Steve Holland    Directed By: Mark Cendrowski
Rating: 5.4 Audience: 18.24
When Sheldon is forced to teach a class, Howard surprises everyone by taking it. Meanwhile, the tension between Penny and Bernadette gives Amy a chance to play both sides. The one-hour eighth season premiere of The Big Bang Theory airs Monday, September 22, 8|7c, on CBS

01 - The Locomotion Interuption

Story By: Jim Reynolds, Maria Ferrari and Tara Hernandez    Directed By: Mark Cendrowski
Rating: 5.4 Audience: 18.03
Leonard and Amy take an unexpected road trip to Arizona to pick up Sheldon. Meanwhile, Penny interviews for a job at Bernadette’s company, and Howard is weirded out by Stuart’s relationship with Mrs. Wolowitz.
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24 - The Status Quo Combustion

Story By: Eric Kaplan, Jim Reynolds and Jeremy Howe Directed By: Mark Cendrowski
Rating: 4.9 Audience: 16.73
Sheldon is forced to confront an uncertain future and considers a major move. Meanwhile, Raj and Emily take it to the next level, and Mrs. Wolowitz’s injury is a major headache for Howard and Bernadette

23 - The Gorilla Dissolution

Story By: Chuck Lorre, Jim Reynolds and Jeremy Howe Directed By: Peter Chakos
Rating: 3.8 Audience: 14.42
A bad day causes Penny to reevaluate her life choices – including Leonard. Meanwhile, Howard and Bernadette struggle to care for Mrs. Wolowitz, and Raj gets relationship advice from Sheldon

22 - The Proton Transmogrification

Story By: Jim Reynolds, Maria Ferrari and Jeremy Howe Directed By: Mark Cendrowski
Rating: 4.5 Audience: 16.07
Professor Proton helps Sheldon cope with grief, while Leonard turns a relationship milestone into a competition with Penny. Meanwhile, Amy and Bernadette make a “Star Wars Day” gift for the guys

21 - The Anything Can Happen Recurrence

Story By: Steven Molaro, Eric Kaplan and Adam Faberman Directed By: Mark Cendrowski
Rating: 4.5 Audience: 16.44
When Sheldon tries to be spontaneous, it leads to unexpected friction between Penny, Amy and Bernadette. Meanwhile, Raj seeks Howard’s help in preparing for a date with Emily

20 - The Relationship Diremption

Story By: Steven Molaro, Bill Prady and Jim Reynolds Directed By: Mark Cendrowski
Rating: 4.7 Audience: 16.29
Sheldon faces a personal crisis after deciding he’s wasting his time with string theory. Meanwhile, a double date between Raj, Emily and the Wolowitzes ends in embarrassment for Howard

19 - The Indecision Amalgamation

Story By: Bill Prady, Eric Kaplan and Jim Reynolds Directed By: Anthony Rich
Rating: 4.9 Audience: 17.73
While Raj is wracked with guilt when he tries to date two women at once, Penny wrestles with whether to take a role in a cheesy movie and Sheldon is torn trying to choose between two gaming systems

18 - The Mommy Observation

Story By: Jim Reynolds & Steve Holland & Maria Ferrari Directed By: Mark Cendrowski
Rating: 4.9 Audience: 17.34
When Sheldon visits his Mom in Houston, he is forced to confront a new reality. Meanwhile, Raj’s ‘Murder Mystery’ party starts some fights within the gang

17 - The Friendship Turbulence

Story By: Steven Molaro, Eric Kaplan and Tara Hernandez Directed By: Mark Cendrowski
Rating: 5.3 Audience: 18.09
After the insults fly, Bernadette tries to broker the peace between Wolowitz and Sheldon. Meanwhile, Penny is offered an embarrassing movie role and Raj asks Amy to write to a woman on his behalf

16 - The Table Polarization

Story By: Steven Molaro, Maria Ferrari and Tara Hernandez Directed By: Gay Linvill
Rating: 5.0 Audience: 17.73
Leonard buys a dining room table and it causes Sheldon to reevaluate the changes in his life. Meanwhile, Wolowitz is offered a chance to go back to space and Bernadette struggles with whether or not to encourage him

15 - The Locomotive Manipulation

Story By: Jim Reynolds, Steve Holland and Tara Hernandez Directed By: Mark Cendrowski
Rating: 5.2 Audience: 17.53
Love is in the air when Sheldon and Amy join Howard and Bernadette for a trip to wine country. Meanwhile, Leonard and Penny must rush Raj’s dog to the vet

14 - The Convention Conundrum

Story By: Eric Kaplan, Jim Reynolds and Adam Faberman Directed By: Mark Cendrowski
Rating:   Audience:  
After the guys can’t get Comic-Con tickets, Sheldon tries to hold his own convention and winds up spending a wild night with James Earl Jones. Meanwhile, the girls see if they can act like “grown-ups"

13 - The Occupation Recalibration

Story By: Eric Kaplan, Maria Ferrari and Tara Hernandez Directed By: Mark Cendrowski
Rating: 5.7 Audience: 20.35
heldon tries to relax after he is forced to take a vacation. Meanwhile, Leonard struggles to be supportive of Penny after she quits her job, and Bernadette seeks Stuart’s help in replacing one of Howard’s comic books

12 - The Hesitation Ramification

Story By: Dave Goetsch, Jim Reynolds and Tara Hernandez Directed By: Mark Cendrowski
Rating: 5.4 Audience: 19.20
Penny puts Leonard on the spot with a bold relationship question

11 - The Cooper Extraction

Story By: Steven Molaro, Eric Kaplan and Maria Ferrari Directed By: Mark Cendrowski
Rating: 5.1 Audience: 17.68
While Sheldon is away in Texas, everyone gathers to decorate the apartment Christmas tree, and they each realize how much he has changed their lives

10 - The Discovery Dissipation

Story By: Eric Kaplan & Jim Reynolds & Maria Ferrari Directed By: Mark Cendrowski
Rating: 4.8 Audience: 15.63
Leonard and Amy help Sheldon cope with the shame he’s feeling after his accidental contribution to science is disproved. Meanwhile, Raj must stay with Howard and Bernadette for a week

09 - The Thanksgiving Decoupling

Story By: Eric Kaplan, Steve Holland and Maria Ferrari Directed By: Mark Cendrowski
Rating: 5.3 Audience: 18.94
Sheldon protests when the gang drags him to Mrs. Wolowitz’s house for Thanksgiving. Meanwhile, Penny and Leonard must deal with a mistake from her past

08 - The Itchy Brain Simulation

Story By: Steven Molaro, Bill Prady and Jim Reynolds Directed By: Mark Cendrowski
Rating: 5.2 Audience: 18.30
Leonard tries to keep Sheldon from overreacting when a past mistake comes to light, but Sheldon punishes Leonard by making him walk a mile in his shoes. Meanwhile, Penny confronts Raj’s ex-girlfriend, Lucy

07 - The Proton Displacement

Story By: Chuck Lorre, Maria Ferrari and Anthony del Broccolo Directed By: Mark Cendrowski
Rating: 4.9 Audience: 16.89
Sheldon feels slighted when Professor Proton seeks advice from Leonard instead of him, and he seeks revenge by befriending a rival science TV host, Bill Nye. Meanwhile, Raj gets jealous when Howard crashes “girls’ night”

06 - The Romance Resonance

Story By: Chuck Lorre, Maria Ferrari and Anthony del Broccolo Directed By: Mark Cendrowski
Rating: 5.2 Audience: 16.98
Sheldon feels slighted when Professor Proton seeks advice from Leonard instead of him, and he seeks revenge by befriending a rival science TV host, Bill Nye. Meanwhile, Raj gets jealous when Howard crashes “girls’ night

05 - The Workplace Proximity

Story By: Steven Molaro, Steve Holland and Maria Ferrari Directed By: Mark Cendrowski
Rating: 5.2 Audience: 17.80
Sheldon must decide how much “Amy time” is too much after she takes a job at his university. Meanwhile, Howard finds himself sleeping on Raj’s couch after a fight with Bernadette

04 - The Raiders Minimization

Story By: Chuck Lorre, Jim Reynolds and Tara Hernandez Directed By: Mark Cendrowski
Rating: 5.1 Audience: 17.64
heldon seeks revenge after Amy ruins one of his favorite movies. Meanwhile, Leonard discovers a way to get Penny to do anything, and Raj and Stuart create online dating profiles

03 - The Scavenger Vortex

Story By: Dave Goetsch, Eric Kaplan & Steve Holland Directed By: Mark Cendrowski
Rating: 5.2 Audience: 18.22
When the entire gang competes in a scavenger hunt designed by Raj, it brings out the best – and worst – in everyone

02 - The Deception Verification

Story By: Chuck Lorre, Eric Kaplan & Jim Reynolds Directed By: Mark Cendrowski
Rating: 5.2 Audience: 18.22
Leonard’s friendship with Sheldon is put to the test when he returns from the North Sea. Meanwhile, Wolowitz’s relationship with his mother causes an unusual threat to his masculinity

01 - The Hofstander Deficiency

Story By: Chuck Lorre, Steve Molaro & Tara Hernandez Directed By: Mark Cendrowski
Rating: 5.5 Audience: 18.99
With Leonard away, Sheldon and Penny spend quality time together sharing intimate secrets. Also, Wolowitz helps Raj get over his ex-girlfriend
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24 - The Bon Voyage Reaction

Story By: Steven Molaro, Steve Holland and Tara Hernandz Directed By: Mark Cendrowski
Rating: 4.8 Audience: 15.48
A new success for Leonard makes Sheldon very jealous and throws Penny for a loop. Meanwhile, Koothrappali pushes Lucy too far in their relationship

23 - The Love Spell Potential

Story By: Chuck Lorre, Jim Reynolds and Maria Ferrari Directed By: Anthony Rich
Rating: 4.9 Audience: 16.30
When the girls’ trip to Vegas falls through, the guys invite them to play Dungeons & Dragons, causing Sheldon and Amy’s relationship to take an unexpected turn. Meanwhile, Koothrappali and Lucy go on a very awkward date

22 - The Proton Resurgence

Story By: Chuck Lorre, Jim Reynolds and Steve Holland Directed By: Mark Cendrowski
Rating: 4.9 Audience: 16.29
Sheldon and Leonard hire Professor Proton, the host of their favorite childhood TV show, to perform. Also, Howard and Bernadette run into trouble babysitting Raj’s dog

21 - The Closure Alternative

Story By: Chuck Lorre, Bill Prady and Tara Hernandez Directed By: Mark Cendrowski
Rating: 4.5 Audience: 15.05
Sheldon feels lost after one of his favorite TV shows gets canceled too soon and Amy tries to help him get over his compulsive need for closure. Meanwhile, Raj discovers a secret about his new love interest, Lucy

20 - The Tenure Turbulence

Story By: Steven Molaro, Eric Kaplan and Maria Ferrari Directed By: Mark Cendrowski
Rating: 5.2 Audience: 17.24
Leonard, Sheldon and Raj fight for tenure at the University, and the competition heats up when the girls get involved

19 - The Closet Reconfiguration

Story By: Chuck Lorre, Jim Reynolds and Maria Ferrari Directed By: Mark Cendrowski
Rating: 4.8 Audience: 15.90
Howard struggles with whether or not he should open a letter from his father, and Leonard and Penny throw a “grown-up” cocktail party at the apartment

18 - The Contractual Obligation Implementation

Story By: Chuck Lorre, Eric Kaplan and Steve Holland Directed By: Mark Cendrowski
Rating: 5.5 Audience: 17.63
Leonard, Sheldon and Wolowitz speak to junior high girls about careers in science. Meanwhile, Koothrappali plans a date with Lucy

17 - The Monster Isolation

Story By: Chuck Lorre, Dave Goetsch and Maria Ferrari Directed By:  Mark Cendrowski
Rating: 5.6 Audience: 17.62
After a terrible date, Koothrappali vows to never leave his apartment. Meanwhile, Penny actually impresses Sheldon with her acting skills

16 - The Tangible Affection Proof

Story By: Chuck Lorre, Bill Prady and Steve Holland Directed By:  Mark Cendrowski
Rating: 5.5 Audience: 17.89
While the guys try to give their significant others the perfect Valentine’s Day, Raj and Stuart throw a “lonely people” party at the comic book store

15 - The Spoiler Alert Segmentation

Story By: Chuck Lorre, Eric Kaplan and Steve Holland Directed By: Mark Cendrowski
Rating: 6.2 Audience: 18.98
When Sheldon and Leonard fight, it affects Penny and Amy’s living arrangements. Meanwhile, Raj takes care of Mrs. Wolowitz while Howard is away

14 - The Cooper/Kripke Inversion

Story By: Chuck Lorre, Eric Kaplan and Anthony Del Broccolo  Directed By: Mark Cendrowski
Rating: 5.4
Audience: 17.76
Sheldon is forced to work with Barry Kripke and faces a crisis of confidence. Meanwhile, Howard and Raj spend $1,000 on action figures of themselves

13 - The Bakersfield Expedition

Story By: Chuck Lorre, Jim Reynolds and Steve Holland Directed By:  Mark Cendrowski
Rating: 6.4 Audience: 20.00
While the guys take a road trip to a comic book convention dressed as “Star Trek: The Next Generation” characters, the girls stay home and try to interpret a comic book

12 - The Egg Salad Equivalency

Story By:  Chuck Lorre, Eric Kaplan and Jim Reynolds Directed By: Mark Cendrowski
Rating: 6.1 Audience: 19.25
Sheldon gets accused of sexual harassment at the University and winds up getting Leonard, Raj and Wolowitz in trouble
Airs January 3

11 - The Santa Simulation

Story By: Chuck Lorre, Eric Kaplan and Steve Holland Directed By: Mark Cendrowski
Rating: 5.4 Audience: 16.77
Sheldon revisits some Christmas memories during a game of Dungeons and Dragons, while Penny, Bernadette and Amy try to find a girl for Koothrappali when he joins the girls for ladies' night

10 - The Fish Guts Displacement

Story By: Chuck Lorre & Bill Prady & Tara Hernandez Directed By: Mark Cendrowski
Rating: 5.2 Audience: 16.94
Sheldon tries to nurse a sick Amy back to health, while Wolowitz prepares for an upcoming fishing trip with his father-in-law

09 - The Parking Spot Escalation

Story By: Chuck Lorre, Eric Kaplan & Adam Faberman Directed By: Peter Chakos
Rating: 5.5 Audience: 17.25
When the University reassigns Sheldon’s parking spot to Wolowitz, their fight affects the whole gang

08 - The 43 Peculiarity

Story By: Chuck Lorre, Dave Goetsch & Anthony Del Broccolo Directed By: Mark Cendrowski
Rating: 5.7 Audience: 17.16
Howard and Raj try to get to the bottom of why Sheldon disappears every afternoon at 2:45. Meanwhile, Leonard and Penny deal with jealousy in their relationship

07 - The Habitation Configuration

Story By: Chuck Lorre, Eric Kaplan and Jim Reynolds Directed By: Mark Cendrowski
Rating: 5.1 Audience: 16.68
Wolowitz struggles with moving out of his mother’s house. Meanwhile, Sheldon is caught in the middle of an argument between Amy and Wil Wheaton

06 - The Extract Obliteration

Story By: Chuck Lorre, Bill Prady and Steve Holland Directed By: Mark Cendrowski
Rating: 5.2 Audience: 15.90
Sheldon’s relationship with Stephen Hawking is threatened over a game of “Words with Friends,” and Penny secretly enrolls in a class at the local college

05 - The Holographic Excitation

Story By: Chuck Lorre, Eric Kaplan and Jeremy Howe Directed By: Mark Cendrowski
Rating: 5.0 Audience: 15.82
The gang celebrates Halloween at Stuart’s comic book store. Meanwhile, Leonard seduces Penny with science

04 - The Re-Entry Minimisation

Story By: Jim Reynolds and Anthony Del Broccolo Directed By: Mark Cendrowski
Rating: 4.8 Audience: 15.73
When Wolowitz returns from space, he doesn’t get the hero’s welcome he expected. Meanwhile, Game Night turns into a battle of the sexes

03 - The Higgs Boson Observation

Story By: Steven Molaro, Dave Goetsch and Steve Holland Directed By: Mark Cendrowski
Rating: 4.5 Audience: 14.23
Amy feels threatened when Sheldon hires a young female assistant, and the pressure of being in space takes its toll on Wolowitz

02 - The Decoupling Fluctation

Story By: Chuck Lorre, Jim Reynolds and Maria Ferrari Directed By: Mark Cendrowski
Rating: 4.9 Audience: 15.18
When Sheldon learns that Penny is thinking about breaking up with Leonard, he tries to intervene. Meanwhile, in space, the other astronauts pick on Howard

01 - The Date Night Variable

Story By: Chuck Lorre, Eric Kaplan and Steve Holland Directed By: Mark Cendrowski
Rating: 5.0 Audience: 15.66
With his friends on dates, Raj must face his loneliness. Also, Wolowitz is caught in an argument between Bernadette and his mom, even while he’s in space
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24 - The Countdown Reflection

Story By: Bill Prady, Eric Kaplan & Steve Holland Directed By: Mark Cendrowski
Rating: 4.4 Audience: 13.72
In the season finale, when Howard and Bernadette decide they want to be married before his NASA launch, the gang rushes to put on a wedding.

23 - The Launch Acceleration

Story By: Chuck Lorre, Steven Molaro & Jim Reynolds Directed By: Mark Cendrowski
Rating: 4.7 Audience: 13.91
When NASA moves up Howard's mission, he must face his fears and Bernadette's dad, thus putting the wedding plans in jeopardy. Meanwhile, Leonard says something surprising to Penny in the bedroom.

22 - The Stag Convergence

Story By: Billy Prady, Steve Holland & Eric Kaplan Directed By: Peter Chakos
Rating: 4.1 Audience: 12.65
The guys throw Howard a bachelor party, and some embarrassing details about his life get posted on the Internet.

21 - The Hawking Excitation

Story By: Bill Prady, Steven Molaro & Steve Holland Directed By: Mark Cendrowski
Rating: 4.4 Audience: 13.29
Sheldon uses any and all means to meet his hero, Dr. Stephen Hawking.

20 - The Transporter Malfunction

Story By: Chuck Lorre, Bill Prady & Maria Ferrari Directed By: Mark Cendrowski
Rating: 4.7 Audience: 13.96
Raj gets quite a surprise when he asks his parents to set him up on a date. Penny buys Leonard and Sheldon a pair of Star Trek keepsake collectibles, not knowing the effect it would have on Sheldon.

19 - The Weekend Vortex

Story By: Chuck Lorre, Bill Prady & Tara Hernandez Directed By: Mark Cendrowski
Rating: 5.1 Audience: 15.04
Sheldon must choose between joining Amy at her aunt's birthday party or playing videogames all weekend with the guys.

18 - The Werewolf Transformation

Story By: Chuck Lorre, Todd Craig & Gary Torvinen Directed By: Mark Cendrowski
Rating: 5.3 Audience: 16.20
Sheldon wreaks havoc when he tries to get a haircut from his regular barber, who is ill. Howard runs into a few problems with astronaut training.

17 - The Rothman Disintegration

Story By: Chuck Lorre, Bill Prady & Steve Holland Directed By: Mark Cendrowski
Rating: 5.1 Audience: 15.65
Sheldon battles Barry Kripke for a coveted office at the university. Penny receives a very unusual gift from Amy.

16 - The Vacation Solution

Story By: Chuck Lorre, Anthony Del Broccolo & Tara Hernandez Directed By: Mark Cendrowski
Rating: 5.6 Audience: 16.21
When the university forces Sheldon to use vacation days, he decides to hang out in Amy's lab. Bernadette wants Howard to sign a prenuptial agreement.

15 - The Friendship Contraction

Story By: Chuck Lorre, Eric Kaplan & Jim Reynolds Directed By: Mark Cendrowski
Rating: 5.5 Audience: 16.54
Leonard signs out of his roommate agreement, reducing himself and Sheldon to mere acquaintances, while Howard tries to think of a cool astronaut nickname for himself.

14 - The Beta Test Initiation

Story By: Chuck Lorre, Steven Molaro & Eric Kaplan Directed By: Mark Cendrowski
Rating: 5.5 Audience: 16.13
Leonard and Penny develop a system to insure their dates go smoothly. Raj finally finds a woman he can talk to - the virtual assistant on his mobile phone.

13 - The Recombination Hypothesis

Story By: Chuck Lorre Directed By: Mark Cendrowski
Rating: 5.3 Audience: 15.83
Leonard and Penny contemplate reviving their romantic relationship. Sheldon's attempt to order Star Trek memorabilia doesn't go as planned.

12 - The Shiny Trinket Maneuver

Story By: Chuck Lorre, Steve Holland & Tara Hernandez Directed By: Mark Cendrowski
Rating: 5.3 Audience: 16.13
Penny must help Sheldon work on his relationship with Amy when he trivializes one of her accomplishments. Bernadette's dislike of children bothers Howard.

11 - The Speckerman Recurrence

Story By: Chuck Lorre, Bill Prady & Steve Holland Directed By: Anthony Rich
Rating: 4.6 Audience: 14.02
Leonard must confront the man who bullied him in high school, while Penny realizes she did her fair share of tormenting in the past.

10 - The Flaming Spittoon Acquisition

Story By: Chuck Lorre, Steven Molaro & Dave Goetsch Directed By: Mark Cendrowski
Rating: 5.3 Audience: 15.05
When Stuart from the comic book store asks Amy on a date, Sheldon considers having a more serious relationship with her. Meanwhile, the guys become obsessed with a new card game involving Wild West heroes and witches.

09 - The Ornithophobia Diffusion

Story By: Chuck Lorre, Dave Goetsch & Anthony Del Broccolo Directed By: Mark Cendrowski
Rating: 5.3 Audience: 15.89
Sheldon must overcome his fear of birds while Leonard and Penny attempt to hang out together strictly as friends.

08 - The Isolation Permutation

Story By: Chuck Lorre, Eric Kaplan & Tara Hernandez Directed By: Mark Cendrowski
Rating: 5.4 Audience: 15.98
Amy is hurt when Bernadette and Penny goes bridesmaid dress shopping without her, so she turns to a reluctant Sheldon for comfort.

07 - The Good Guy Fluctuation

Story By: Chuck Lorre, Dave Goetsch & Maria Ferrari Directed By: Mark Cendrowski
Rating: 4.6 Audience: 14.54
Sheldon tries to get into the spirit of Halloween by trying to scare the guys after they prank him. A comic book artist is interested in Leonard.

06 - The Rhinitis Revelation

Story By: Chuck Lorre, Eric Kaplan & Steve Holland Directed By: Howard Murray
Rating: 5.1 Audience: 14.93
Sheldon is upset when his mom comes to visit but refuses to cook for him and attend physics lectures.

05 - The Russian Rocket Reaction

Story By: Bill Prady, Steven Molaro & Jim Reynolds Directed By: Mark Cendrowski
Rating: 4.4 Audience: 13.26
Sheldon takes offense when Leonard wants to attend a party with Star Trek's Wil Wheaton and Brent Spiner, and Bernadette tries to block Howard's opportunity to go into outer space.

04 - The Wiggly Finger Catalyst

Story By: Chuck Lorre, David Goetsch & Anthony Del Broccolo Directed By: Mark Cendrowski
Rating: 4.5 Audience: 13.92
Penny sets up Raj with a deaf friend, not knowing that she's actually a gold digger, and Sheldon decides to let his minor decisions rest on the roll of the dice.

03 - The Pulled Groin Extrapolation

Story By: Bill Prady, Steven Molaro & Dave Goetsch Directed By: Mark Cendrowski
Rating: 4.9 Audience: 14.74
While Sheldon stays at home to play with his new train set, Leonard and Amy learn a lot about each other when he goes as her "plus one" to a wedding. Howard and Bernadette spend the weekend with his mother.

02 - The Infestation Hypothesis

Story By: Bill Prady, Steven Molaro & Maria Ferrari Directed By: Mark Cendrowski
Rating: 5.1 Audience: 14.94
Sheldon has health issues with Penny's new chair. Amy gets inadvertently caught in the middle of a fight between Sheldon and Penny. Leonard tries to add some spice to his long-distance relationship with Priya.

01 - The Skank Reflex Analysis

Story By: Eric Kaplan, Maria Ferrari & Anthony Del Broccolo Directed By: Mark Cendrowski
Rating: 4.9 Audience: 14.30
The gang deals with the fallout from Penny and Raj's night together. Amy counsels Penny when she considers moving back to Nebraska due to her failing acting career. Sheldon takes charge of the paintball team.
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24 - The Roommate Transmogrification

Story By:  Chuck Lorre, Steven Molaro & Eddie Gorodetsky Directed By: Mark Cendrowski
Rating: 3.6 Audience: 11.30
Raj moves in with Sheldon after hearing Leonard and Priya engage in a Star Trek fantasy in his apartment. Bernadette receives her doctorate, and the gang teases Howard about not having one.

23 - The Engagement Reaction

Story By: Bill Prady, Eric Kaplan & Jim Reynolds Directed By: Howard Murray
Rating: 3.4 Audience: 10.78
Howard believes that his mom suffered a heart attack because he told her that he's marrying Bernadette, and Sheldon freaks out over germs after he accidentally drinks Leonard's water.

22 - The Wildebeest Implementation

Story By: Chuck Lorre, Steven Molaro & Eric Kaplan Directed By: Mark Cendrowski
Rating: 3.2 Audience: 10.50
While Sheldon invents a three-player chess game, Bernadette uses a double date to spy on Leonard and Priya's relationship, and Raj tries a new drug to treat his social anxiety.

21 - The Agreement Dissection

Story By: Bill Prady, Dave Goetsch & Eddie Gorodetsky Directed By: Mark Cendrowski
Rating: 3.3 Audience: 10.71
When Priya finds a loophole in the roommate agreement to throw Sheldon out for the night, Penny, Amy, and Bernadette take Sheldon to a nightclub.

20 - The Herb Garden Germination

Story By: Chuck Lorre, Eric Kaplan & Eddie Gorodetsky Directed By: Mark Cendrowski
Rating: 3.7 Audience: 11.40
Sheldon and Amy secretly experiment on the gang by spreading rumors. Howard and Bernadette's relationship reaches an important milestone.

19 - The Zarnecki Incursion

Story By: Chuck Lorre, Steven Molaro & Maria Ferrari Directed By: Peter Chakos
Rating: 3.7 Audience: 11.92
The gang goes all out to help Sheldon find the person responsible for hacking his online gaming account, but Priya is beginning to get fed up with Leonard's childish behavior.

18 - The Prestidigitation Approximation

Story By: Bill Prady, Steve Holland & Eddie Gorodetsky Directed By: Mark Cendrowski
Rating: 3.8 Audience: 12.06
Priya forces Leonard to choose between a relationship with her or a friendship with Penny. A magic trick by Howard has Sheldon fooled.

17 - The Toast Derivation

Story By: Bill Prady, Dave Goetsch & Maria Ferrari Directed By: Mark Cendrowski
Rating: 3.8 Audience: 12.35
Sheldon becomes concerned when everybody begins to hang out at Raj's apartment and discovers Leonard is the center of the group.

16 - The Cohabitation Formulation

Story By: Chuck Lorre, Lee Aronsohn & Dave Goetsch Directed By: Mark Cendrowski
Rating: 3.7 Audience: 12.41
Bernadette makes Howard choose between herself and his mother, and how will Penny react when Leonard begins seeing Raj's sister again when she's back in town?

15 - The Benefactor Factor

Story By: Bill Prady, Lee Aronsohn & Dave Goetsch Directed By: Mark Cendrowski
Rating: 3.9 Audience: 12.79
To secure needed funding for their school, Sheldon convinces Leonard to get friendly with a wealthy benefactor.

14 - The Thespian Catalyst

Story By: Chuck Lorre, Lee Aronsohn & Jim Reynolds Directed By: Mark Cendrowski
Rating: 4.3 Audience: 13.83
To improve his skills as an instructor, Sheldon asks Penny to give him acting lessons. Meanwhile, Raj begins having impure fantasies about Bernadette.

13 - The Love Car Displacement

Story By: Chuck Lorre, Bill Prady & Dave Goetsch Directed By: Anthony Rich
Rating: 4.2 Audience: 13.63
Tension runs high as the entire gang spends the weekend together at a science convention.

12 - The Bus Pants Utilization

Story By: Chuck Lorre, Lee Aronsohn & Maria Ferrari Directed By: Mark Cendrowski
Rating: 4.4 Audience: 13.98
Leonard has an idea for a new smartphone app and asks the guys for help. However, Sheldon tries to take over the project, and Leonard fires him.

11 - The Justice League Recombination

Story By: Chuck Lorre, Lee Aronsohn & Maria Ferrari Directed By: Mark Cendrowski
Rating: 4.0 Audience: 13.24
The guys enter a costume contest as members of the Justice League...and convince Penny's new boyfriend to join them.

10 - The Alien Parasite Hypothesis

Story By: Chuck Lorre, Steven Molaro & Steve Holland Directed By: Mark Cendrowski
Rating: 3.9 Audience: 12.03
Amy finds she has sexual feelings for Penny's ex, while Koothrappali and Wolowitz try to prove who would be the better superhero.

09 - The Boyfriend Complexity

Story By: Chuck Lorre, Lee Aronsohn & Jim Reynolds Directed By: Mark Cendrowski
Rating: 4.3 Audience: 13.02
Penny asks Leonard to pose as her boyfriend when her father visits. Howard, Raj, and Bernadette are up all night looking through a telescope.

08 - The 21 Second Excitation

Story By: Chuck Lorre, Lee Aronsohn & Maria Ferrari Directed By: Mark Cendrowski
Rating: 4.2 Audience: 13.11
The guys camp out all night waiting to see a new movie while Penny and Bernadette invite Amy to her first slumber party.

07 - The Apology Insufficiency

Story By: Chuck Lorre, Lee Aronsohn & Steven Molaro Directed By: Mark Cendrowski
Rating: 4.7 Audience: 14.00
An FBI agent interviews everyone when Howard needs to obtain a security clearance. Sheldon is beside himself when Howard refuses to accept his apology.

06 - The Irish Pub Formulation

Story By: Chuck Lorre, Lee Aronsohn & Steven Molaro Directed By: Mark Cendrowski
Rating: 4.2 Audience: 13.04
Leonard tries to keep everyone from finding out that he spent the night with Raj's sister, but Sheldon finds out and concocts an elaborate story to help him keep the secret from Raj.

05 - The Desperation Emanation

Story By: Bill Prady, Lee Aronsohn & Dave Goetsch Directed By: Mark Cendrowski
Rating: 4.1 Audience: 13.05
Sheldon is scared that he is in a relationship when Amy asks him to meet her mother, and Leonard asks Wolowitz and Bernadette to set him up because he is the only person in the group without a girlfriend.

04 - The Hot Troll Deviation

Story By: Chuck Lorre, Steven Molaro & Adam Faberman Directed By: Mark Cendrowski
Rating: 4.3 Audience: 12.57
Wolowitz tries to get help from Penny, Katie Sackhoff and George Takei to get back together with Bernadette, while Raj and Sheldon quarrel over office space as they work together on a project

03 - The Zazzy Substitution

Story By: Chuck Lorre, Bill Prady & Jim Reynolds Directed By: Mark Cendrowski
Rating: 4.1 Audience: 12.59
Following his breakup with Amy, the gang becomes concerned with Sheldon's obsessive search for non-human companionship, and they call his mother to intervene.

02 - The Cruciferous Vegetable Amplification

Story By: Bill Prady, Lee Aronsohn & Steve Holland Directed By: Mark Cendrowski
Rating: 4.4 Audience: 13.06
When Sheldon calculates the technology to download his consciousness into a robot won't be invented soon enough, he desperately tries to find a way to increase his lifespan.

01 - The Robotic Manipulation

Story By: Chuck Lorre, Lee Aronsohn & Dave Goetsch Directed By: Mark Cendrowski
Rating: 4.9 Audience: 14.03
Penny ends up tagging along on Sheldon's first-ever date with Amy Farrah Fowler, while Wolowitz finds an unusual use for the new robotic arm he's created.
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23 - The Lunar Excitation

Story By: Chuck Lorre, Bill Prady & Maria Ferrari Directed By: Peter Chakos
Rating: 5.3 Audience: 15.02
Penny has a night of angry, drunken sex with Leonard, which Leonard soon misinterprets as something other than a mistake. Meanwhile, Wolowitz and Koothrappali search for Sheldon's perfect match online.

22 - The Staircase Implementation

Story By: Lee Aronsohn, Steven Molaro & Steve Holland Directed By: Mark Cendrowski
Rating: 5.5 Audience: 15.02
After Leonard and Sheldon get in a fight over the thermostat, Leonard goes to Penny's apartment and tells her about how he met Sheldon for the first time and how they became roommates...and what happened to the elevator.

21 - The Plimpton Stimulation

Story By: Chuck Lorre, Bill Prady & Lee Aronsohn Directed By: Mark Cendrowski
Rating: 5.3 Audience: 13.73
Sheldon and Penny are both disturbed and disappointed when Leonard hooks up with Sheldon's visiting female physicist friend.

20 - The Spaghetti Catalyst

Story By: Chuck Lorre, Bill Prady, Lee Aronsohn & Steven Molaro Directed By: Anthony Rich
Rating: 4.6 Audience: 11.63
With Leonard and Penny now broken up, Sheldon is forced to go behind Leonard's back to spend time with her.

19 - The Wheaton Recurrence

Story By: Chuck Lorre, Steven Molaro, Nichole Lorre & Jessica Ambrosetto Directed By: Mark Cendrowski
Rating: 5.1 Audience: 13.39
Sheldon takes on his newest nemesis, Star Trek's Wil Wheaton, in bowling. Leonard and Penny's relationship comes to a crossroad.

18 - The Pants Alternative

Story By: Chuck Lorre, Bill Prady & Steve Holland Directed By: Mark Cendrowski
Rating: 5.2 Audience: 13.41
Sheldon needs the gang's help in overcoming his fear of public speaking when he receives an award.

17 - The Precious Fragmentation

Story By: Lee Aronsohn, Eric Kaplan & Maria Ferrari Directed By: Mark Cendrowski
Rating: 5.9 Audience: 16.31
When the guys find an actual ring from the "Lord of the Rings" trilogy at a garage sale, their friendship is threatened.

16 - The Excelsior Acquisition

Story By: Chuck Lorre, Lee Aronsohn & Steven Molaro Directed By: Peter Chakos
Rating: 5.9 Audience: 15.73
Sheldon misses an opportunity to get Stan Lee's autograph because he has to make an appearance in traffic court.

15 - The Large Hadron Collision

Story By: Chuck Lorre, Steven Molaro & Jim Reynolds Directed By: Mark Cendrowski
Rating:

6.0

Audience: 16.26
When Leonard must travel to Switzerland on Valentine's Day to visit the CERN laboratory, Sheldon uses any and all means to be his guest instead of Penny.

14 - The Einstein Approximation

Story By: Lee Aronsohn, Dave Goetsch & Steve Holland Directed By: Mark Cendrowski
Rating: 5.4 Audience: 15.51
Sheldon acts even more strangely when he is stumped by a difficult physics question, so he is forced to resort to Einstein-inspired measures to unclutter his mind and solve the problem.

13 - The Bozeman Reaction

Story By: Bill Prady, Lee Aronsohn & Jim Reynolds Directed By: Mark Cendrowski
Rating: 5.2 Audience: 14.99
When their apartment is robbed, Leonard and Sheldon turn to their friends to create a state-of-the-art security system.

12 - The Psychic Vortex

Story By: Lee Aronsohn & Steven Molaro Directed By: Mark Cendrowski
Rating: 5.7 Audience: 15.81
Raj talks Sheldon into being his wingman at a university mixer. Leonard has trouble dealing with Penny consulting a psychic.

11 - The Maternal Congruence

Story By: Steven Molaro, Richard Rosenstock & Maria Ferrari Directed By: Mark Cendrowski
Rating: 5.6 Audience: 15.58
Leonard's mother makes a visit to his dismay and Sheldon's delight.

10 - The Gorilla Experiment

Story By: Chuck Lorre, Richard Rosenstock & Steve Holland Directed By: Mark Cendrowski
Rating: 5.6 Audience: 14.38
Sheldon attempts to help Penny understand physics to impress Leonard, and Wolowitz becomes jealous when his new girlfriend takes an interest in Leonard's research.

09 - The Vengeance Formulation

Story By: Chuck Lorre & Maria Ferrari
Teleplay: Richard Rosenstock, Jim 
Directed By: Mark Cendrowski
Rating: 5.2 Audience: 14.13
Sheldon vows payback after Kripke humiliates him on the radio. Howard gets advice concerning his relationship with Bernadette...from "Battlestar Galactica's" Katee Sackhoff.

08 - The Adhesive Duck Deficiency

Story By: Chuck Lorre, Bill Prady & David Goetsch Directed By: Mark Cendrowski
Rating: 5.0 Audience: 13.23
Penny separates her shoulder in the bathtub, and is forced to turn to Sheldon for help. Meanwhile, the rest of the guys accidentally get stoned in the desert while waiting for a meteor shower

07 - The Guitarist Amplification

Story By: Chuck Lorre & Lee Aronsohn Directed By: Mark Cendrowski
Rating: 4.7 Audience: 12.79
Sheldon is forced to play peacemaker when Leonard and Penny have an argument, mainly because their fighting is bringing back repressed childhood memories.

06 - The Cornhusker Vortex

Story By: Bill Prady & Maria Ferrari Directed By: Mark Cendrowski
Rating: 4.7 Audience: 12.73
To blend in better with several of Penny's friends from back home, Leonard learns about football...from Sheldon. Meanwhile, a loss in a kite war threatens to end Raj and Howard's friendship.

05 - The Creepy Candy Coating Corollary

Story By: Chuck Lorre & Bill Prady Directed By: Mark Cendrowski
Rating: 5.3 Audience: 13.47
Wolowitz begs Penny to set him up with one of her friends; Sheldon seeks payback against Wil Wheaton.

04 - The Pirate Solution

Story By: Steve Holland Directed By: Mark Cendrowski
Rating: 5.0 Audience: 13.07
Raj must find a new job or be sent back to India, but Sheldon has a solution, which leaves Leonard and Penny dealing with Howard as third wheel.

03 - The Gothowitz Deviation

Story By: Lee Aronsohn & Richard Rosenstock Directed By: Mark Cendrowski
Rating: 4.5 Audience: 12.25
Sheldon attempts to covertly alter Penny's habits, while Howard and Raj try their luck meeting women at a Goth-style club.

02 - The Jiminy Conjecture

Story By: Jim Reynolds Directed By: Mark Cendrowski
Rating: 5.3 Audience: 13.27
Leonard and Penny's first night together goes awkwardly. Sheldon and Howard wager on the species of a cricket.

01 - The Electric Can Opener Fluctuation

Story By: Steven Molaro Directed By: Mark Cendrowski
Rating: 4.7 Audience: 12.96
After returning from the North Pole, a conflict among the guys sends Sheldon back to Texas and interferes with Leonard's reunion with Penny.
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23 - The Monopolar Expedition

Story By: Eric Kaplan & Richard Rosenstock Directed By: Mark Cendrowski
Rating: 3.6 Audience: 9.81
Penny gets upset when she finds out Leonard and the guys plan to work at the North Pole for the summer.

22 - The Classified Materials Turbulence

Story By: Chuck Lorre & Lee Aronsohn Directed By: Mark Cendrowski
Rating: 3.4 Audience: 9.24
Penny's second date with Stuart has significant implications for Leonard. Howard enlists the guys' help with one of his NASA projects.

21 - The Vegas Renormalization

Story By: Jessica Ambrosetti, Nicole Lorre & Andrew Roth Directed By: Mark Cendrowski
Rating: 3.4 Audience: 9.31
After being dumped by Leslie, Howard heads to Las Vegas with Leonard and Raj, leaving Penny to deal with Sheldon, who has locked himself out of the apartment.

20 - The Hofstadter Isotope

Story By: David Goetsch Directed By: Mark Cendrowski
Rating: 3.8 Audience: 10.13
Leonard is so upset when a friend from the comic book store begins dating Penny that he convinces Howard and Raj to take him to a bar so that he can pick up a woman of his own.

19 - The Dead Hooker Juxtaposition

Story By: Steven Molaro Directed By: Mark Cendrowski
Rating: 3.8 Audience: 9.77
Penny becomes jealous when a gorgeous new neighbor attracts the guys' attention.

18 - The Work Song Nanocluster

Story By: Dave Goetsch & Richard Rosenstock Directed By: Peter Chakos
Rating: 3.7 Audience: 9.76
Sheldon's assistance with Penny's home-based business leads to disaster.

17 - The Terminator Decoupling

Story By: Tim Doyle & Stephen Engel Directed By: Mark Cendrowski
Rating: 3.6 Audience: 9.46
On a train trip to San Francisco, the boys debate on how to meet sci-fi star Summer Glau, who is on board with them.

16 - The Cushion Saturation

Story By: Bill Prady & Lee Aronsohn Directed By: Mark Cendrowski
Rating: 3.9 Audience: 10.94
Howard hooks up with Leslie, while Penny accidentally ruins Sheldon's spot on the couch.

15 - The Maternal Capacitance

Story By: Richard Rosenstock & Steven Molaro Directed By: Mark Cendrowski
Rating: 4.6 Audience: 13.11
Sheldon hits it off with Leonard's psychoanalyst mother, but she drives Leonard and Penny to the bottle.

14 - The Financial Permeability

Story By: Richard Rosenstock & Eric Kaplan Directed By: Mark Cendrowski
Rating: 4.1 Audience: 10.89
Penny cannot afford to pay her rent, so Sheldon and Leonard each come up with unique ways to help her out.

13 - The Friendship Algorithm

Story By: Chuck Lorre & Steven Molaro Directed By: Mark Cendrowski
Rating: 4.0 Audience: 11.10
Sheldon tries to make friends with a despised colleague, with the hopes that it will get him access to a coveted computer in the lab.

12 - The Killer Robot Instability

Story By: Daley Haggar & Steven Molaro Directed By: Mark Cendrowski
Rating: 4.4 Audience: 11.81
Howard becomes depressed after Penny makes a cruel statement about his love life, while the rest of the guys prepare for a grudge killer robot duel against an obnoxious colleague at the university.

11 - The Bath Item Gift Hypothesis

Story By: Eric Kaplan & Stephen Engel Directed By: Mark Cendrowski
Rating: 4.2 Audience: 11.42
Much to Lenonard's disappointment, Penny suddenly develops an interest in science when a sexy new physicist joins the lab. Meanwhile, Sheldon struggles to find an appropriate Christmas gift for Penny.

10 - The Vartabedian Conundrum

Story By: Richard Rosenstock & Bill Prady Directed By: Mark Cendrowski
Rating: 3.7 Audience: 10.80
Leonard is the last one to realize that Stephanie has moved in with him. And when he finds out, he becomes worried that they are moving too fast

09 - The White Asparagus Triangulation

Story By: Stephen Engel & Richard Rosenstock Directed By: Mark Cendrowski
Rating: 3.9 Audience: 10.19
Sheldon tries to help move Leonard's new relationship along, because his track record with women has been less than successful. But will he cause more trouble than good?

08 - The Lizard Spock Expansion

Story By: Jennifer Glickman & David Goetsch Directed By: Mark Cendrowski
Rating: 3.9 Audience: 9.76
Howard and Leonard's friendship could be at an end when Leonard steals Howard's new woman from him.

07 - The Panty Piñata Polarization

Story By: Jennifer Glickman & Steven Molaro Directed By: Mark Cendrowski
Rating: 3.7 Audience: 9.66
Penny plans revenge when Sheldon bans her from the guys' apartment, while Howard and Rajesh use the latest technology to try to find the house being used in "America's Next Top Model."

06 - The Cooper Nowitzki Theorem

Story By: Stephen Engel & Daley Haggar Directed By: Mark Cendrowski
Rating: 3.5 Audience: 9.28
Sheldon becomes cozy with a female graduate student who is infatuated with him, but nobody can figure out whether they're in a relationship--including Sheldon.

05 - The Euclid Alternative

Story By: Lee Aronsohn & David Goetsch Directed By: Mark Cendrowski
Rating: 3.6 Audience: 9.36
The gang tries to teach Sheldon how to drive.

04 - The Griffin Equivalency

Story By: Chuck Lorre & Bill Prady Directed By: Mark Cendrowski
Rating: 3.6 Audience: 9.32
After being featured in a People magazine article, Raj becomes full of himself and alienates his friends. However, his newfound fame does get him a date with Penny.

03 - The Barbarian Sublimation

Story By: Steve Molaro & Eric Kaplan Directed By: Mark Cendrowski
Rating: 3.5 Audience: 8.76
Sheldon turns Penny on to online gaming, and then she refuses to turn it off after becoming addicted.

02 - The Codpiece Topology

Story By: Bill Prady & Lee Aronsohn Directed By: Mark Cendrowski
Rating: 3.5 Audience: 8.76
After seeing Penny with her new boyfriend, Leonard turns to Leslie for comfort. The move angers Sheldon, who considers Leslie his comic book-style "arch enemy."

01 - The Bad Fish Paradigm

Story By: Steven Molaro & David Goetsch Directed By: Mark Cendrowski
Rating: 3.6 Audience: 9.36
Leonard is concerned when his date with Penny ends abruptly and she starts blowing him off. When told the truth, Sheldon would rather move out than keep Penny's reasons a secret from Leonard.
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17 - The Tangerine Factor

Story By: Chuck Lorre & Bill Prady Directed By: Mark Cendrowski
Rating: 2.6 Audience: 7.34
After Penny breaks up with her new guy, she agrees to go out on a date with Leonard. However, both of them have reservations about the date soon after agreeing to it.

16 - The Peanut Reaction

Story By: Bill Prady & Lee Aronsohn Directed By: Mark Cendrowski
Rating: 2.7 Audience: 7.79
When Penny and the guys learn that Leonard has never had a birthday party, they decide to try to throw a surprise party for him.

15 - The Shiksa Indeterminacy/The Pork Chop Indeterminacy 

Story By: Chuck Lorre Directed By: Mark Cendrowski
Rating: 2.6 Audience: 8.07
Sheldon's sexy twin sister arrives in town from Texas, and all of Sheldon's friends fight over who will get to be with her.

14 - The Nerdvana Annihilation

Story By:  Bill Prady Directed By: Mark Cendrowski
Rating: 2.8 Audience: 8.07
Penny gets mad at Leonard because the guys' new "time machine" causes her to miss work. Leonard is so devastated that he vows to give up all of his nerd memorabilia.

13 - The Bat Jar Conjecture

Story By: Stephen Engel & Jennifer Glickman Directed By: Mark Cendrowski
Rating: 2.9 Audience: 7.51
Sheldon becomes so intent on demonstrating his intellectual superiority over his Physics Bowl teammates that they boot him, and replace him with his nemesis.

12 - The Jerusalem Duality

Story By: Jennifer Glickman & Stephen Engel Directed By: Mark Cendrowski
Rating: 2.9 Audience: 7.69
Sheldon is threatened when a new 15-year-old prodigy who is smarter than him joins the lab, so the guys come up with a plan to get rid of him.

11 - The Pancake Batter Anomaly

Story By: Chuck Lorre & Lee Aronsohn Directed By: Mark Cendrowski
Rating: 3.1 Audience: 8.68
Sheldon is sick, and Leonard and the guys sneak out to a "Planet of the Apes" movie marathon to get out of taking care of him--which leaves Penny as the only person to whom the needy Sheldon can turn.

10 - The Loobenfeld Decay

Story By: Chuck Lorre Directed By: Mark Cendrowski
Rating: 3.4 Audience: 8.63
Leonard lies to Penny so that he and Sheldon can get out of watching her perform. However, Sheldon believes that the lie has too many loose ends, so he comes up with a new, unnecessarily complex one to replace it.

09 - The Cooper Hofstadter Polarization

Story By:  Bill Prady & Stephen Engel Directed By: Joel Murray
Rating: 3.7 Audience: 9.11
Leonard and Sheldon's friendship is put to the test when Leonard wants to present a paper they co-authored at a physics convention, but Sheldon does not.

08 - The Grasshopper Experiment

Story By: Dave Goetsch & Steven Molaro Directed By: Ted Wass
Rating: 3.3 Audience: 9.32
Rajesh's parents, communicating from India by Web cam, arrange for him to go out with another Indian woman in the hopes of marriage, but his date turns out to have more in common with Sheldon.

07 - The Dumpling Paradox

Story By: Chuck Lorre & Bill Prady Directed By: Mark Cendrowski
Rating: 3.8 Audience: 9.67
When Howard hooks up with Penny's old friend, it ruins the nights on which all of the guys play the game "Halo."

06 - The Middle Earth Paradigm

Story By: Dave Goetsch Directed By: Mark Cendrowski
Rating: 3.6 Audience: 8.92
The guys are invited to Penny's Halloween costume party. During the party, Leonard has a run-in with Penny's ex-boyfriend.

05 - The Hamburger Postulate

Story By: Jennifer Glickman Directed By: Andrew D. Weyman
Rating: 3.1 Audience: 8.81
Leonard and his colleague Leslie spend the night together. But Leslie tells Leonard after the fact that she's only interested in a one-night stand.

04 - The Luminous Fish Effect

Story By: Chuck Lorre & Bill Prady Directed By: Mark Cendrowski
Rating: 3.2 Audience: 8.15
Sheldon's Christian-fundamentalist mother visits to get him out of the funk he's in after he is fired for being disrespectful toward his new boss.

03 - The Fuzzy Boots Corollary

Story By: Chuck Lorre & Bill Prady Directed By: Mark Cendrowski
Rating: 3.4 Audience: 8.36
Leonard gets upset when he discovers that Penny is seeing a new guy, so he tries to trick her into going on a date with him.

02 - The Big Bran Hypothesis

Story By: Chuck Lorre & Bill Prady Directed By: Mark Cendrowski
Rating: 3.4 Audience: 8.58
Penny is furious and more than a little freaked out with Leonard and Sheldon when they sneak into her apartment overnight, and clean it while she is sleeping.

01 - Pilot

Story By: Chuck Lorre & Bill Prady Directed By: James Burrows
Rating: 3.7 Audience: 9.52
A pair of brilliant theoretical physicists meet a woman who shows them how little they know about the real world.
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