The Big Bang Theory Wiki

Season 6 of The Big Bang Theory premiered on September 27, 2012, and ended on May 16, 2013. All of the seven regular actors on the show returned to their respective roles. The first episode taping began on August 14, 2012. It was announced that starting from this season, Kevin Sussman, who plays Stuart Bloom, would be a regular, though he is later demoted back to recurring. Starting with Howard's trip to the International Space Station, Penny is pushed deeper into her relationship with Leonard when Sheldon's graduate assistant Alex Jensen is interested in Leonard. The season ends with Leonard leaving for the North Sea to help Stephen Hawking prove a theory, and Raj undergoing a major social transition.


Main Cast

Recurring Cast

Guest Cast


Episode (Series) Episode (Season/Ep#) Title Original Air Date Directed By Description
112 601 The Date Night Variable September 27, 2012 Mark Cendrowski Sheldon, Amy, Leonard, and Penny all have dates, but Sheldon invites Raj to his date with Amy, upsetting Amy. As a result, Raj interrupts Leonard and Penny's, only to get kicked out when he tells Penny to acknowledge her feelings for Leonard, prompting him to go to the comic book store instead. Meanwhile, a still-in-space Howard gets in a dilemma with his wife and mother over where he will choose to live once he returns to Earth.
113 602 The Decoupling Fluctuation October 4, 2012 Mark Cendrowski Penny tries to figure out her feelings for Leonard with the help of Bernadette and Amy. Sheldon tries to get Penny to stay in the relationship. Stuart becomes Raj's new hang-out buddy to fill the gap left by Howard, and gets accepted into the social group by Sheldon. Meanwhile, Howard gets bullied by his fellow astronauts.
114 603 The Higgs Boson Observation October 11, 2012 Mark Cendrowski Sheldon hires an attractive grad student named Alex Jensen to help him. Amy gets jealous and asks Penny to spy on her at Caltech, only to find out that Alex is flirting with Leonard instead. Meanwhile, Howard informs Bernadette that he needs to stay in space for an additional 7-10 days.
115 604 The Re-Entry Minimization October 18, 2012 Mark Cendrowski Howard finally returns to Earth, only to discover that changes have happened that leave him dejected, such as Stuart replacing him as Raj's best friend and mother having an affair with his dentist. Bernadette is also too sick to comfort him. Meanwhile, Sheldon, Leonard, Penny, and Amy take part in a girls versus guys competition.
116 605 The Holographic Excitation October 25,2012 Mark Cendrowski Stuart wants to organize a Halloween party at his comic book store so Raj steps up to become the party planner. Bernadette has to deal with an annoying Howard who cannot stop talking about space. Penny decides to learn more about Leonard's job, and Sheldon and Amy are at odds on what to wear to the Halloween party.
117 606 The Extract Obliteration November 1, 2012 Mark Cendrowski Sheldon is excited when Stephen Hawking accepts his invitation to play a popular online game with him. Meanwhile, Penny considers telling Leonard about the fact that she is going back to school by taking a history class at a community college.
118 607 The Habitation Configuration November 8, 2012 Mark Cendrowski Sheldon tapes another episode of "Fun With Flags", only this time, the episode will focus on Star Trek flags so he brings his friend Wil Wheaton as a guest. Problems arise when Amy and Wil appear to dislike each other and Sheldon is torn on whose side to take. Meanwhile, Howard prepares to finally move out of mother's house to live with Bernadette.
119 608 The 43 Peculiarity November 15, 2012 Mark Cendrowski Raj and Howard are determined to find out what Sheldon is doing for twenty minutes every day in a storage room in the Caltech basement. Leonard is jealous of an English student that is working on a college project with Penny. She gets very angry at Leonard and makes a startling admission.
120 609 The Parking Spot Escalation Novembver 29, 2012 Peter Chakos After Howard gets himself a car, a fight occurs between him and Sheldon after it is made clear that his parking spot at the university actually belongs to Sheldon even though Sheldon doesn't own a car. The conflict eventually stirs hostility between Bernadette and Amy. Both parties resort to dastardly actions to get revenge.
121 610 The Fish Guts Displacement December 6, 2012 Mark Cendrowski Howard and Bernadette have dinner with her parents and Howard ends up invited on her father's weekend fishing trip. Penny gives the guys a lesson in the art of fishing. Amy isn't feeling well and Sheldon overcomes his initial objections to take care of his girlfriend.
122 611 The Santa Simulation December 13, 2012 Mark Cendrowski The guys decide to have a male night of Dungeons and Dragons which does not sit well with their better halves. The girls get dressed up and head out to a nightclub together taking Raj along.
123 612 The Egg Salad Equivalency January 3, 2013 Mark Cendrowski Sheldon gets all the guys before the Human Resources Department when he tries to talk to Alex about her advances to Leonard. Alex's actions also make Penny feel insecure and Leonard more confident.
124 613 The Bakersfield Expedition January 10, 2013 Mark Cendrowski While the guys attend the Bakersfield Comic-Con dressed as Star Trek: The Next Generation characters, the girls decide to explore their world of comic books and get deeper than they expected. Leonard's car is stolen while they are dressed in Star Trek costumes.
125 614 The Cooper/Kripke Inversion January 31, 2013 Mark Cendrowski Howard's nerd hobby gets him into money troubles. Sheldon is forced to work with Kripke. After Kripke's paper is better than Sheldon's, Sheldon ends up spreading rumors about a sexual relationship with Amy
126 615 The Spoiler Alert Segmentation February 7, 2013 Mark Cendrowski With Leonard mad at Sheldon, he moves in with Penny. Amy notes that she would be the perfect roommate for Sheldon since she knows him so well and he wouldn't have to break in someone else. Sheldon and Penny are not happy with these arrangements. Raj is trapped in the Wolowitz house with Howard's lonely mother.
127 616 The Tangible Affection Proof February 14, 2013 Mark Cendrowski The couples are getting ready for Valentine's Day. Leonard, Penny, Howard and Bernadette are going to dinner. Sheldon and Amy are trying to get the perfect gifts for each other. Raj and Stuart are planning a singles only party at The Comic Book Store.
128 617 The Monster Isolation February 21, 2013 Mark Cendrowski Sheldon has Penny as a guest on a "Fun with Flags" episode and she gets him to attend her acting class' presentation of "A Streetcar Named Desire". Raj becomes depressed for not having any girlfriend or relationship wio someone..
129 618 The Contractual Obligation Implementation March 7, 2013 Mark Cendrowski Raj and Lucy have their first date meeting in a library and texting to each other. The guys have to promote science careers for women at Howard's old middle school, while the girls go to Disneyland and get made up as Disney Princesses.
130 619 The Closet Reconfiguration March 14, 2013 Anthony Rich Sheldon rearranges Howard and Bernadette's closet and finds an unopened letter from his father sent for his 18th birthday. Penny and Leonard have a formal dinner party instead of take-out food.
131 620 The Tenure Turbulence April 18, 2013 Mark Cendrowski Competition between the guys increases when a slot for a tenured professor opens up and they start to schmooze the tenure committee members that include Janine Davis from Human Resources, whom Sheldon has crossed paths with before.
132 621 The Closure Alternative April 25, 2013 Mark Cendrowski Amy works on Sheldon's obsession to complete everything, Leonard tries to get Penny interested in "Buffy the Vampire Slayer" and Raj discusses with Lucy what she put in her blog about him.
133 622 The Proton Resurgence May 2, 2013 Mark Cendrowski The host of the children's science show Professor Proton is available for children's birthday parties, so Sheldon hires him since he was one of his childhood heroes. Howard and Bernadette watch Raj's dog for the weekend and she gets lost.
134 623 The Love Spell Potential May 9, 2013 Anthony Rich After an aborted girls' trip to Vegas, everyone ends up playing Dungeons and Dragons together. Raj leaves after he finds that Lucy is free and he pushes her to do things that scare her. In the game, Penny casts a love spell on Sheldon and Amy's characters which gets Amy very upset because they are treating her and Sheldon's relationship as a joke.
135 624 The Bon Voyage Reaction May 16, 2013 Mark Cendrowski Leonard joins a team on a four-month overseas expedition which affects both Sheldon and Penny. Raj invites Lucy to meet his friends and attend a going away party. Amy volunteers to have dinner with Raj and Lucy.