Seasons & episodes
S4 · E1The Robotic Manipulation 8.9 / 10 · 1 published rating 2010-09-23 · 21 min
Penny tags along on Sheldon's first ever date; Wolowitz finds a new use for a robotic arm.
S4 · E2The Cruciferous Vegetable Amplification 8.7 / 10 · 1 published rating 2010-09-30 · 21 min
Realizing he will not live long enough to download his consciousness into a robot body, Sheldon tries to extend his life span.
S4 · E3The Zazzy Substitution 7.8 / 10 · 1 published rating 2010-10-07 · 21 min
The guys are concerned as Sheldon searches for an alternative to human companionship.
S4 · E4The Hot Troll Deviation 8.0 / 10 · 1 published rating 2010-10-14 · 20 min
An embarrassing secret of Wolowitz's comes to light, while Sheldon and Raj have a small war at work.
S4 · E5The Desperation Emanation 7.9 / 10 · 1 published rating 2010-10-21 · 21 min
Leonard realizes he’s the only one without a girlfriend, while Sheldon wants to get rid of his.
S4 · E6The Irish Pub Formulation 8.3 / 10 · 1 published rating 2010-10-28 · 22 min
Leonard keeps an affair a secret from Sheldon, Howard and Raj.
S4 · E7The Apology Insufficiency 8.3 / 10 · 1 published rating 2010-11-04 · 21 min
Sheldon's answers during an FBI interview put Wolowitz's security clearance in jeopardy.
S4 · E8The 21-Second Excitation 8.0 / 10 · 1 published rating 2010-11-11 · 19 min
While the guys camp in line for a long-awaited movie screening, Penny and Bernadette invite Amy to her first slumber party.
S4 · E9The Boyfriend Complexity 8.3 / 10 · 1 published rating 2010-11-18 · 21 min
Penny asks Leonard to lie to her father, while Howard, Raj and Bernadette pull an all-nighter at a telescope.
S4 · E10The Alien Parasite Hypothesis 8.5 / 10 · 1 published rating 2010-12-09 · 20 min
Amy finds she has sexual feelings for Penny's ex, while Koothrappali and Wolowitz try to prove who would be the better superhero.
S4 · E11The Justice League Recombination 9.5 / 10 · 1 published rating 2010-12-16 · 20 min
The guys find a "super" use for Penny's new boyfriend, Zack, when they enter a costume contest as the Justice League.
S4 · E12The Bus Pants Utilization 7.9 / 10 · 1 published rating 2011-01-06 · 21 min
Leonard's idea for a smartphone app derails his friendship with Sheldon.
S4 · E13The Love Car Displacement 8.6 / 10 · 1 published rating 2011-01-20 · 21 min
Bernadette runs into her ex-boyfriend while attending a science event with Wolowitz.
S4 · E14The Thespian Catalyst 7.7 / 10 · 1 published rating 2011-02-03 · 21 min
Hoping it will make him a better teacher, Sheldon has Penny give him acting lessons. Raj has fantasies about a friend's girlfriend.
S4 · E15The Benefactor Factor 8.3 / 10 · 1 published rating 2011-02-10 · 20 min
A wealthy donor to the university makes Leonard consider how far he's willing to go for the sake of science.
S4 · E16The Cohabitation Formulation 8.0 / 10 · 1 published rating 2011-02-17 · 20 min
As Wolowitz contemplates taking things with Bernadette to the next level, Leonard rekindles his relationship with Raj's sister.
S4 · E17The Toast Derivation 7.9 / 10 · 1 published rating 2011-02-24 · 21 min
Sheldon becomes concerned when everybody begins to hang out at Raj's apartment and discovers Leonard is the center of the group.
S4 · E18The Prestidigitation Approximation 7.9 / 10 · 1 published rating 2011-03-10 · 21 min
Sheldon is baffled by Wolowitz's magic trick. Meanwhile, Leonard realizes dating Priya may make it impossible to continue being friends with Penny.
S4 · E19The Zarnecki Incursion 8.9 / 10 · 1 published rating 2011-03-31 · 21 min
Sheldon's online-game account is hacked by Todd Zarnecki, who then proceeds to steal all his items prompting the guys to go on a quest to retrieve them. Penny, Bernadette and Amy discuss how Penny groomed Leonard to be willing to try various things and more adventurous boyfriend... for some other woman — Priya.
S4 · E20The Herb Garden Germination 8.5 / 10 · 1 published rating 2011-04-07 · 21 min
Sheldon and Amy decide to start several rumors about the others as a test. Meanwhile, Howard takes his relationship with Bernadette to even higher level.
S4 · E21The Agreement Dissection 8.8 / 10 · 1 published rating 2011-04-28 · 21 min
When Leonard spends too much time in the shower with Priya, Sheldon charges Leonard with two violations of the roommate agreement. However, before he can get too far, Priya uses her skills as a lawyer to nullify the charges due to the agreement's vague wording, much to Sheldon's dismay. When the guys take advantage of Priya's skills in order to eat Greek food on pizza night, Sheldon goes to Penny, who invites him to a girls' night out with Amy and Bernadette, which Sheldon agrees to after Penny mentions that they may be talking trash about Priya. After the girls drink some cocktails, they decide to take Sheldon dancing, which Sheldon reluctantly goes along with. After dancing, Sheldon takes an intoxicated Amy back to her apartment and as well as talking about Priya, meets a monkey who is addicted to smoking cigarettes. Amy tells Sheldon not to give in to Priya's law skills, before kissing him and going to her bathroom to vomit.
S4 · E22The Wildebeest Implementation 8.0 / 10 · 1 published rating 2011-05-05 · 21 min
Raj attempts to cure his social anxiety disorder while Penny uses Bernadette to spy on Leonard and his girlfriend.
S4 · E23The Engagement Reaction 8.0 / 10 · 1 published rating 2011-05-12 · 20 min
When Howard finally breaks the news to his mom that he's engaged to Bernadette, it lands her in the hospital.
S4 · E24The Roommate Transmogrification 8.1 / 10 · 1 published rating 2011-05-19 · 21 min
When Bernadette receives her PhD, Wolowitz feels emasculated. Raj and Leonard swap places and Penny does something she's regrets.