The Bakersfield Expedition: The guys get all dressed up for a photo opportunity at a Star Trek location but end up stranded in the desert. (S6 Ep13) [AD,S]
The Cooper/Kripke Inversion: Sheldon is forced to work on the same project as his nemesis, Barry Kripke. Howard and Raj spend a fortune on personalised action figures. (S6 Ep14) [AD,S]
The Bakersfield Expedition: The guys get all dressed up for a photo opportunity at a Star Trek location but end up stranded in the desert. (S6 Ep13) [AD,S]
The Cooper/Kripke Inversion: Sheldon is forced to work on the same project as his nemesis, Barry Kripke. Howard and Raj spend a fortune on personalised action figures. (S6 Ep14) [AD,S]
The Line Substitution Solution: Sheldon pays Stuart to spend the afternoon shopping with Amy so that he can queue up to see a special film screening instead. (S9 Ep23) [AD,S]
The Convergence Convergence: Conflict arises when Leonard's recently divorced parents and Sheldon's devoutly religious mother are all in town at the same time. (S9 Ep24) [AD,S]
The Line Substitution Solution: Sheldon pays Stuart to spend the afternoon shopping with Amy so that he can queue up to see a special film screening instead. (S9 Ep23) [AD,S]
The Convergence Convergence: Conflict arises when Leonard's recently divorced parents and Sheldon's devoutly religious mother are all in town at the same time. (S9 Ep24) [AD,S]
The Electric Can Opener Fluctuation: Leonard's attempts to woo Penny are constantly thwarted. Sheldon heads to Texas after learning his friends meddled with his expedition data. (S3 Ep1) [AD,S]
The Jiminy Conjecture: Leonard and Penny feel awkward around each other after their romantic liaison, while Sheldon and Howard take bets to determine a species of cricket. (S3 Ep2) [AD,S]
The Gothowitz Deviation: Sheldon tries to modify Penny's behaviour, and rewards her with chocolate when she does what he wants, while Howard and Raj go to a goth nightclub. (S3 Ep3) [AD,S]
The Pirate Solution: Raj must find a job or he'll be sent back to India, so he accepts an offer of work from Sheldon. Leonard and Penny try to get some time for themselves. (S3 Ep4) [AD,S]
The Plimpton Stimulation: When Sheldon meets a famous physicist online, he invites her over to the apartment, where she spends her time flirting with Leonard. (S3 Ep21) [AD,S]
The Lunar Excitation: Raj registers Sheldon for online dating and finds the perfect match: the female version of Sheldon. Penny seduces Leonard while she's drunk. (S3 Ep23) [AD,S]
The Plimpton Stimulation: When Sheldon meets a famous physicist online, he invites her over to the apartment, where she spends her time flirting with Leonard. (S3 Ep21) [AD,S]
The Robotic Manipulation: Penny tags along to Sheldon's first date with a woman he's been texting for months. Howard finds a new use for a robotic arm. (S4 Ep1) [AD,S]
The Lunar Excitation: Raj registers Sheldon for online dating and finds the perfect match: the female version of Sheldon. Penny seduces Leonard while she's drunk. (S3 Ep23) [AD,S]
The Robotic Manipulation: Penny tags along to Sheldon's first date with a woman he's been texting for months. Howard finds a new use for a robotic arm. (S4 Ep1) [AD,S]
The Spoiler Alert Segmentation: After Sheldon and Leonard have a row, Leonard attempts to move in with Penny, even though she isn't ready for such a big step. (S6 Ep15) [AD,S]
The Tangible Affection Proof: Annoyed at being forced to celebrate Valentine's Day when he hates it, Sheldon delegates the task of buying Amy's gift to his assistant. (S6 Ep16) [AD,S]
The Spoiler Alert Segmentation: After Sheldon and Leonard have a row, Leonard attempts to move in with Penny, even though she isn't ready for such a big step. (S6 Ep15) [AD,S]
The Tangible Affection Proof: Annoyed at being forced to celebrate Valentine's Day when he hates it, Sheldon delegates the task of buying Amy's gift to his assistant. (S6 Ep16) [AD,S]
The Conjugal Conjecture: The gang face an awkward morning after Sheldon's mother and Leonard's father share an evening together. Penny's family arrive in town. (S10 Ep1) [AD,S]
The Military Miniaturization: Howard has a meeting with Air Force representative Colonel Williams about the gyroscope he invented with Leonard and Sheldon. (S10 Ep2) [AD,S]
The Conjugal Conjecture: The gang face an awkward morning after Sheldon's mother and Leonard's father share an evening together. Penny's family arrive in town. (S10 Ep1) [AD,S]
The Military Miniaturization: Howard has a meeting with Air Force representative Colonel Williams about the gyroscope he invented with Leonard and Sheldon. (S10 Ep2) [AD,S]
The Creepy Candy Coating Corollary: Due to a childhood snub, Sheldon is irked when Star Trek actor Wil Wheaton (guest starring as himself) takes part in the same contest as him. (S3 Ep5) [AD,S]
The Cornhusker Vortex: Sheldon teaches Leonard about American football so that he can try to fit in with Penny's friends. And Raj and Sheldon have a kite-fighting contest. (S3 Ep6) [AD,S]
The Guitarist Amplification: Sheldon is annoyed when Leonard and Penny argue about Penny's male friend staying over and he has to act as peacemaker. (S3 Ep7) [AD,S]
The Creepy Candy Coating Corollary: Due to a childhood snub, Sheldon is irked when Star Trek actor Wil Wheaton (guest starring as himself) takes part in the same contest as him. (S3 Ep5) [AD,S]
The Adhesive Duck Deficiency: Leonard, Raj and Howard go on a camping trip that alters their minds. Penny dislocates her shoulder when she slips in the shower. (S3 Ep8) [AD,S]
The Cornhusker Vortex: Sheldon teaches Leonard about American football so that he can try to fit in with Penny's friends. And Raj and Sheldon have a kite-fighting contest. (S3 Ep6) [AD,S]
The Guitarist Amplification: Sheldon is annoyed when Leonard and Penny argue about Penny's male friend staying over and he has to act as peacemaker. (S3 Ep7) [AD,S]
The Adhesive Duck Deficiency: Leonard, Raj and Howard go on a camping trip that alters their minds. Penny dislocates her shoulder when she slips in the shower. (S3 Ep8) [AD,S]
The Cruciferous Vegetable Amplification: Sheldon realises that he won't live long enough to download his consciousness into a robot body, so he tries to extend his lifespan. (S4 Ep2) [AD,S]
The Zazzy Substitution: The guys are concerned when a heartbroken Sheldon starts bulk buying cats after he breaks up with Amy, so Leonard tries to get Sheldon's mother to visit. (S4 Ep3) [AD,S]
The Hot Troll Deviation: An embarrassing secret of Howard's comes to light as he tries to win back Bernadette. Sheldon and Raj have trouble working together. (S4 Ep4) [AD,S]
The Cruciferous Vegetable Amplification: Sheldon realises that he won't live long enough to download his consciousness into a robot body, so he tries to extend his lifespan. (S4 Ep2) [AD,S]
The Desperation Emanation: Leonard realises he's the only one of the gang with no girlfriend. Sheldon wants to get rid of his when she hatches a plan for him to meet her mother. (S4 Ep5) [AD,S]
The Zazzy Substitution: The guys are concerned when a heartbroken Sheldon starts bulk buying cats after he breaks up with Amy, so Leonard tries to get Sheldon's mother to visit. (S4 Ep3) [AD,S]
The Hot Troll Deviation: An embarrassing secret of Howard's comes to light as he tries to win back Bernadette. Sheldon and Raj have trouble working together. (S4 Ep4) [AD,S]
The Desperation Emanation: Leonard realises he's the only one of the gang with no girlfriend. Sheldon wants to get rid of his when she hatches a plan for him to meet her mother. (S4 Ep5) [AD,S]
The Monster Isolation: After a terrible date with Lucy, Raj vows never to leave his flat again. Sheldon asks Penny to help him record a new episode of Fun with Flags. (S6 Ep17) [AD,S]
The Contractual Obligation Implementation: Leonard, Sheldon and Howard are forced to volunteer for a university committee. Raj plans a stress-free date with Lucy. (S6 Ep18) [AD,S]
The Monster Isolation: After a terrible date with Lucy, Raj vows never to leave his flat again. Sheldon asks Penny to help him record a new episode of Fun with Flags. (S6 Ep17) [AD,S]
The Contractual Obligation Implementation: Leonard, Sheldon and Howard are forced to volunteer for a university committee. Raj plans a stress-free date with Lucy. (S6 Ep18) [AD,S]
The Dependence Transcendence: Tensions rise when the guys struggle to complete their Air Force project on time and are forced to work around the clock. (S10 Ep3) [AD,S]
The Cohabitation Experimentation: When Amy's flat is flooded, she has to move out while it is being repaired and proposes a 'cohabitation experiment' with Sheldon. (S10 Ep4) [AD,S]
The Dependence Transcendence: Tensions rise when the guys struggle to complete their Air Force project on time and are forced to work around the clock. (S10 Ep3) [AD,S]
The Cohabitation Experimentation: When Amy's flat is flooded, she has to move out while it is being repaired and proposes a 'cohabitation experiment' with Sheldon. (S10 Ep4) [AD,S]
The Maternal Congruence: Leonard is horrified when his mother turns up unannounced for a Christmas visit, and then he finds out that Sheldon knew about her divorce before him. (S3 Ep11) [AD,S]
The Psychic Vortex: Sheldon and Raj go to a university party where Raj lusts after a girl called Abby. Leonard regrets telling Penny that he disapproves of her belief in psychics. (S3 Ep12) [AD,S]
The Maternal Congruence: Leonard is horrified when his mother turns up unannounced for a Christmas visit, and then he finds out that Sheldon knew about her divorce before him. (S3 Ep11) [AD,S]
The Psychic Vortex: Sheldon and Raj go to a university party where Raj lusts after a girl called Abby. Leonard regrets telling Penny that he disapproves of her belief in psychics. (S3 Ep12) [AD,S]
The Irish Pub Formulation: A visit from Raj's sister Priya creates tension among the guys, especially when Leonard asks Sheldon to conceal his romantic past with her. (S4 Ep6) [AD,S]
The Apology Insufficiency: Leonard thinks his dating problems are due to a lack of confidence, and vows to be self-assured around attractive women. Howard is called by the FBI. (S4 Ep7) [AD,S]
The 21-Second Excitation: The gang's plans to attend a film screening are scuppered by Sheldon's nemesis Wil Wheaton. Penny and Bernadette invite Amy to her first slumber party. (S4 Ep8) [AD,S]
The Irish Pub Formulation: A visit from Raj's sister Priya creates tension among the guys, especially when Leonard asks Sheldon to conceal his romantic past with her. (S4 Ep6) [AD,S]
The Boyfriend Complexity: When Penny's father visits, Leonard discovers that her parents still think that he and Penny are a couple, so he takes advantage of the situation. (S4 Ep9) [AD,S]
The Apology Insufficiency: Leonard thinks his dating problems are due to a lack of confidence, and vows to be self-assured around attractive women. Howard is called by the FBI. (S4 Ep7) [AD,S]
The 21-Second Excitation: The gang's plans to attend a film screening are scuppered by Sheldon's nemesis Wil Wheaton. Penny and Bernadette invite Amy to her first slumber party. (S4 Ep8) [AD,S]
The Boyfriend Complexity: When Penny's father visits, Leonard discovers that her parents still think that he and Penny are a couple, so he takes advantage of the situation. (S4 Ep9) [AD,S]
The Closet Reconfiguration: When Howard and Bernadette get Sheldon to organise their untidy closet, Sheldon finds an unopened letter from Howard's long-absent father. (S6 Ep19) [AD,S]
The Closet Reconfiguration: When Howard and Bernadette get Sheldon to organise their untidy closet, Sheldon finds an unopened letter from Howard's long-absent father. (S6 Ep19) [AD,S]
The Hot Tub Contamination: Leonard and Penny intervene when Sheldon and Amy have an argument. Howard and Bernadette are disturbed by unexpected guests. (S10 Ep5) [AD,S]
The Fetal Kick Catalyst: Penny meets her fans at a comic book convention. Sheldon and Amy host brunch at Penny's flat. Howard makes an impulsive purchase. (S10 Ep6) [AD,S]
The Veracity Elasticity: Leonard is upset when he finds out that Penny has been moving his collectables out of Sheldon's old room and into storage behind his back. (S10 Ep7) [AD,S]
The Hot Tub Contamination: Leonard and Penny intervene when Sheldon and Amy have an argument. Howard and Bernadette are disturbed by unexpected guests. (S10 Ep5) [AD,S]
The Brain Bowl Incubation: Sheldon tries to convince Amy that they should procreate. Raj feels embarrassed about what the new woman in his life does for a living. (S10 Ep8) [AD,S]
The Fetal Kick Catalyst: Penny meets her fans at a comic book convention. Sheldon and Amy host brunch at Penny's flat. Howard makes an impulsive purchase. (S10 Ep6) [AD,S]
The Veracity Elasticity: Leonard is upset when he finds out that Penny has been moving his collectables out of Sheldon's old room and into storage behind his back. (S10 Ep7) [AD,S]
The Brain Bowl Incubation: Sheldon tries to convince Amy that they should procreate. Raj feels embarrassed about what the new woman in his life does for a living. (S10 Ep8) [AD,S]
The Romance Recalibration: Penny thinks that Leonard has stopped making an effort in their relationship, so she decides to go away for a spa weekend with Amy. (S10 Ep13) [AD,S]
The Bitcoin Entanglement: Sheldon seeks revenge when the guys cut him out of a potentially valuable investment. A secret about Leonard and Penny is revealed. (S11 Ep9) [AD,S]
The Tesla Recoil: Leonard and Howard learn that Sheldon went to work with the military behind their backs. Bernadette thinks Ruchi's trying to steal her job. (S11 Ep8) [AD,S]
The Geology Methodology: Sheldon and Bert collaborate on a research project, but Sheldon feels embarrassed to be associated with the study of geology. (S11 Ep7) [AD,S]
The Retraction Reaction: Leonard angers the university during an embarrassing interview. Amy and Bernadette must hide their success from Sheldon and Howard. (S11 Ep2) [AD,S]
The Proposal Proposal: Amy must decide whether or not to marry Sheldon and gives him an answer to his proposal. Howard and Bernadette struggle with some unexpected news. (S11 Ep1) [AD,S]
The Recollection Dissipation: Sheldon collaborates on two projects - one with Leonard and Howard, plus another with Amy - pushing himself to the limit. (S10 Ep20) [AD,S]
The Collaboration Fluctuation: Leonard, Penny and Raj settle into their new living arrangement, and Sheldon expresses an interest in Amy's professional life. (S10 Ep19) [AD,S]
The Escape Hatch Identification: Leonard and Penny offer Sheldon's old room to Raj when he's forced to move out of his flat, leading to unexpected conflict. (S10 Ep18) [AD,S]
The Locomotion Reverberation: Leonard and Howard distract Sheldon with a trip to a historic railway when he slows their progress on the guidance system. (S10 Ep15) [AD,S]
The Emotion Detection Automation: Sheldon tests a new invention after hearing that it could help him to read people's emotions. Raj seeks dating advice. (S10 Ep14) [AD,S]
The Romance Recalibration: Penny thinks that Leonard has stopped making an effort in their relationship, so she decides to go away for a spa weekend with Amy. (S10 Ep13) [AD,S]
The Holiday Summation: After spending Christmas apart, the gang gather at Penny and Leonard's flat and hear about Sheldon and Amy's terrible trip to Texas. (S10 Ep12) [AD,S]
The Birthday Synchronicity: Sheldon and Amy try to celebrate her birthday with an intimate night at home but are interrupted when Bernadette goes into labour. (S10 Ep11) [AD,S]
The Geology Elevation: Sheldon can't contain his jealousy when he hears that his university colleague, Bert the geologist, has won a prestigious fellowship. (S10 Ep9) [AD,S]
The Brain Bowl Incubation: Sheldon tries to convince Amy that they should procreate. Raj feels embarrassed about what the new woman in his life does for a living. (S10 Ep8) [AD,S]
The Veracity Elasticity: Leonard is upset when he finds out that Penny has been moving his collectables out of Sheldon's old room and into storage behind his back. (S10 Ep7) [AD,S]
The Fetal Kick Catalyst: Penny meets her fans at a comic book convention. Sheldon and Amy host brunch at Penny's flat. Howard makes an impulsive purchase. (S10 Ep6) [AD,S]
The Hot Tub Contamination: Leonard and Penny intervene when Sheldon and Amy have an argument. Howard and Bernadette are disturbed by unexpected guests. (S10 Ep5) [AD,S]
The Cohabitation Experimentation: When Amy's flat is flooded, she has to move out while it is being repaired and proposes a 'cohabitation experiment' with Sheldon. (S10 Ep4) [AD,S]
The Dependence Transcendence: Tensions rise when the guys struggle to complete their Air Force project on time and are forced to work around the clock. (S10 Ep3) [AD,S]
The Military Miniaturization: Howard has a meeting with Air Force representative Colonel Williams about the gyroscope he invented with Leonard and Sheldon. (S10 Ep2) [AD,S]
The Conjugal Conjecture: The gang face an awkward morning after Sheldon's mother and Leonard's father share an evening together. Penny's family arrive in town. (S10 Ep1) [AD,S]
The Geology Elevation: Sheldon can't contain his jealousy when he hears that his university colleague, Bert the geologist, has won a prestigious fellowship. (S10 Ep9) [AD,S]
The Brain Bowl Incubation: Sheldon tries to convince Amy that they should procreate. Raj feels embarrassed about what the new woman in his life does for a living. (S10 Ep8) [AD,S]
The Veracity Elasticity: Leonard is upset when he finds out that Penny has been moving his collectables out of Sheldon's old room and into storage behind his back. (S10 Ep7) [AD,S]
The Fetal Kick Catalyst: Penny meets her fans at a comic book convention. Sheldon and Amy host brunch at Penny's flat. Howard makes an impulsive purchase. (S10 Ep6) [AD,S]
The Hot Tub Contamination: Leonard and Penny intervene when Sheldon and Amy have an argument. Howard and Bernadette are disturbed by unexpected guests. (S10 Ep5) [AD,S]
The Cohabitation Experimentation: When Amy's flat is flooded, she has to move out while it is being repaired and proposes a 'cohabitation experiment' with Sheldon. (S10 Ep4) [AD,S]
The Dependence Transcendence: Tensions rise when the guys struggle to complete their Air Force project on time and are forced to work around the clock. (S10 Ep3) [AD,S]
The Military Miniaturization: Howard has a meeting with Air Force representative Colonel Williams about the gyroscope he invented with Leonard and Sheldon. (S10 Ep2) [AD,S]
The Conjugal Conjecture: The gang face an awkward morning after Sheldon's mother and Leonard's father share an evening together. Penny's family arrive in town. (S10 Ep1) [AD,S]
The Convergence Convergence: Conflict arises when Leonard's recently divorced parents and Sheldon's devoutly religious mother are all in town at the same time. (S9 Ep24) [AD,S]
The Line Substitution Solution: Sheldon pays Stuart to spend the afternoon shopping with Amy so that he can queue up to see a special film screening instead. (S9 Ep23) [AD,S]
The Fermentation Bifurcation: The gang run into Penny's ex-boyfriend, Zack, at a wine bar. Bernadette, who can't drink, hangs out with Sheldon. (S9 Ep22) [AD,S]
The Viewing Party Combustion: During a get-together to watch TV at the flat, a minor argument between Sheldon and Leonard escalates into a heated debate. (S9 Ep21) [AD,S]
The Big Bear Precipitation: Sheldon shares a secret about Leonard when the two of them go on a weekend trip to a cabin in the country with Amy and Penny. (S9 Ep20) [AD,S]
The Positive Negative Reaction: When Bernadette makes a big announcement, Howard becomes convinced that he needs to start earning more money. (S9 Ep16) [AD,S]
The Valentino Submergence: Sheldon and Amy host a special live Valentine's Day episode of their internet show Fun with Flags. Leonard and Penny grapple with getting older. (S9 Ep15) [AD,S]
The Convergence Convergence: Conflict arises when Leonard's recently divorced parents and Sheldon's devoutly religious mother are all in town at the same time. (S9 Ep24) [AD,S]
The Line Substitution Solution: Sheldon pays Stuart to spend the afternoon shopping with Amy so that he can queue up to see a special film screening instead. (S9 Ep23) [AD,S]
The Fermentation Bifurcation: The gang run into Penny's ex-boyfriend, Zack, at a wine bar. Bernadette, who can't drink, hangs out with Sheldon. (S9 Ep22) [AD,S]
The Viewing Party Combustion: During a get-together to watch TV at the flat, a minor argument between Sheldon and Leonard escalates into a heated debate. (S9 Ep21) [AD,S]
The Big Bear Precipitation: Sheldon shares a secret about Leonard when the two of them go on a weekend trip to a cabin in the country with Amy and Penny. (S9 Ep20) [AD,S]
The Solder Excursion Diversion: Sheldon makes a surprise revelation when Amy buys him a new laptop. Leonard and Howard lie to their wives to avoid an errand. (S9 Ep19) [AD,S]
The Application Deterioration: Leonard, Sheldon and Howard run into problems when they file for a patent. Emily reaches out to Raj after their break-up. (S9 Ep18) [AD,S]
The Celebration Experimentation: The gang persuade Sheldon to celebrate his birthday and invite a few special guests along to his party, in the 200th episode. (S9 Ep17) [AD,S]