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 Ep4/24) [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 Ep3/24) [AD,S]
The Fortification Implementation: When Sheldon and Amy build a blanket fort, they come to a major crossroads in their relationship. Howard meets his half-brother. (S8 Ep20/24) [AD,S]
The Skywalker Incursion: When Leonard and Sheldon are invited to speak at Berkeley, they take a detour during the journey to try to meet one of their idols. (S8 Ep19/24) [AD,S]
The Leftover Thermalization: A power cut at Mrs Wolowitz's house defrosts the last meal she prepared before her death, so the gang consume it in her honour. (S8 Ep18/24) [AD,S]
The Colonization Application: Amy learns that Sheldon has applied to take part in a one-way mission to colonise Mars. Leonard surprises Penny with a gift. (S8 Ep17/24) [AD,S]
The Status Quo Combustion: With potential changes affecting different aspects of his personal and professional life, Sheldon is forced to confront an uncertain future. (S7 Ep24/24) [AD,S]
The Gorilla Dissolution: Penny re-evaluates her life, including taking a big step with Leonard, while Howard and Bernadette struggle to look after Mrs Wolowitz. (S7 Ep23/24) [AD,S]
The Proton Transmogrification: Sheldon struggles to process his feelings of grief when his idol Professor Proton passes away. The gang gather to celebrate Star Wars Day. (S7 Ep22/24) [AD,S]
The Anything Can Happen Recurrence: Penny and Leonard distract Sheldon from his career problems by reinstating Anything Can Happen Thursday. Raj asks for Howard's advice. (S7 Ep21/24) [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 Ep2/24) [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 Ep1/24) [AD,S]
The Intimacy Acceleration: When the gang hear about an experiment designed to make participants fall in love, Sheldon and Penny put it to the test as a joke. (S8 Ep16/24) [AD,S]
The Comic Book Store Regeneration: The gang prepare for the reopening of Stuart's comic book shop. Penny teaches Sheldon to 'let it go' when he is irritated. (S8 Ep15/24) [AD,S]
The Troll Manifestation: Leonard and Sheldon co-publish a physics paper but are forced to defend themselves against negative comments from an online critic. (S8 Ep14/24) [AD,S]
The Anxiety Optimization: When Sheldon gets stuck in a rut with his research, he asks his friends to cure his mental block by raising his stress levels. (S8 Ep13/24) [AD,S]
The Relationship Diremption: Sheldon wonders whether he's wasting his time with his study of string theory. Raj and Emily go on a double date with Howard and Bernadette. (S7 Ep20/24) [AD,S]
The Indecision Amalgamation: Raj has a dating dilemma. Penny can't decide whether to accept a role in a terrible film. Sheldon chooses between two gaming systems. (S7 Ep19/24) [AD,S]
The Mommy Observation: Sheldon pays a surprise visit to his mother in Houston and is forced to confront a new reality. Raj throws a murder mystery-themed dinner party. (S7 Ep18/24) [AD,S]
The Friendship Turbulence: In an attempt to improve their strained friendship, Howard invites Sheldon to visit NASA with him. Penny is upset when her car breaks down. (S7 Ep17/24) [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 Ep23/23) [AD,S]
The Staircase Implementation: Leonard tells Penny about how he and Sheldon became friends, and the origins of the roommate agreement. (S3 Ep22/23) [AD,S]
The Space Probe Disintegration: Howard tries to calm a stressed Raj, who is anxiously awaiting the arrival of some data from a space probe that he helped launch. (S8 Ep12/24) [AD,S]
The Clean Room Infiltration: Amy hosts a Victorian Christmas Eve dinner, complete with party games. Raj, Leonard and Howard have pigeon problems. (S8 Ep11/24) [AD,S]
The Champagne Reflection: Sheldon and Amy record the final episode of their internet show Fun with Flags. Penny tells Bernadette how her colleagues really feel about her. (S8 Ep10/24) [AD,S]
The Septum Deviation: When Leonard has to have minor surgery on his nose, Sheldon is the one who seems to need sympathy. Raj is upset when his parents split up. (S8 Ep9/24) [AD,S]
The Table Polarization: Leonard buys a dining table for the flat but Sheldon objects to such a big change inside his home. Meanwhile, Howard gets the chance to return to space. (S7 Ep16/24) [AD,S]
The Locomotive Manipulation: Love is in the air when Amy convinces Sheldon to join her for a romantic train trip to Napa Valley to celebrate Valentine's Day. (S7 Ep15/24) [AD,S]
The Convention Conundrum: After the guys miss out on Comic-Con tickets, Sheldon decides to hold his own comic book convention. The girls take tea at a swanky hotel. (S7 Ep14/24) [AD,S]
The Occupation Recalibration: Penny quits her job at the restaurant to pursue her acting career full-time. Bernadette accidentally destroys one of Howard's comics. (S7 Ep13/24) [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 Ep21/23) [AD,S]
The Spaghetti Catalyst: Sheldon hides his friendship with Penny from Leonard, but it isn't long before his double life is exposed. Can he remain friends with both of them? (S3 Ep20/23) [AD,S]
The Prom Equivalency: The girls decide to re-enact their high school proms with their current partners on the roof of the apartment building. (S8 Ep8/24) [AD,S]
The Misinterpretation Agitation: A smitten doctor turns up at Penny's door after her flirtatious sales techniques for the pharmaceutical company work a little too well. (S8 Ep7/24) [AD,S]
The Expedition Approximation: Sheldon and Raj try to find out if they could survive a dark-matter research expedition in a salt mine by simulating the conditions in a tunnel. (S8 Ep6/24) [AD,S]
The Focus Attenuation: The guys attempt to invent something of scientific importance but only come up with new and enjoyable ways to procrastinate. (S8 Ep5/24) [AD,S]
The Hesitation Ramification: Penny's big TV acting break hits the cutting-room floor, so Leonard does his best to comfort her, which leads her to ask him a bold question. (S7 Ep12/24) [AD,S]
The Cooper Extraction: Sheldon has to go back to Texas when his sister goes into labour. While he's away, the gang gather at the flat to decorate the Christmas tree. (S7 Ep11/24) [AD,S]
The Discovery Dissipation: Sheldon feels guilty when he gets attention for his accidental discovery of a new element. Raj stays with Howard and Bernadette for a week. (S7 Ep10/24) [AD,S]
The Thanksgiving Decoupling: Howard takes the gang to his mother's house for Thanksgiving to protect himself from his grumpy father-in-law who has also been invited. (S7 Ep9/24) [AD,S]
The Wheaton Recurrence: Leonard tells Penny that he loves her. The gang go bowling and find that Sheldon's enemy, Wil Wheaton, is playing in the opposing team. (S3 Ep19/23) [AD,S]
The Pants Alternative: Sheldon is awarded a prestigious prize but is scared of collecting the award at a ceremony because he knows he'll have to make a speech. (S3 Ep18/23) [AD,S]
The Hook-Up Reverberation: Raj's honesty about his past comes back to haunt him when his girlfriend Emily gives Penny the cold shoulder. The guys consider an investment. (S8 Ep4/24) [AD,S]
The First Pitch Insufficiency: Howard's nervous when NASA ask him to throw the first pitch at a baseball game. Sheldon claims his and Amy's relationship is the best in the gang. (S8 Ep3/24) [AD,S]
The Junior Professor Solution: When Sheldon has to teach a course at the university, Howard enrols in his class. Tension brews between Penny and Bernadette. (S8 Ep2/24) [AD,S]
The Locomotion Interruption: Leonard and Amy take an impromptu road trip to Arizona to pick up Sheldon when his epic railway journey ends in chaos. Penny has an interview. (S8 Ep1/24) [AD,S]
The Itchy Brain Simulation: Leonard worries that Sheldon will overreact when he confesses that he failed to return a DVD to the rental shop seven years earlier. (S7 Ep8/24) [AD,S]
The Proton Displacement: Sheldon is jealous when Professor Proton asks Leonard to read his latest publication, so he befriends a TV personality from a rival science show. (S7 Ep7/24) [AD,S]
The Romance Resonance: Sheldon is mortified when he stumbles upon an important scientific breakthrough by accident. Howard makes a romantic gesture to Bernadette. (S7 Ep6/24) [AD,S]
The Workplace Proximity: Amy tells Sheldon she's been asked to work on a project at his university, but the guys insist that it will be bad for their relationship. (S7 Ep5/24) [AD,S]