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The Big Bang Theory Season 4 Episodes
Season 4 Episode Guide
24 Episodes 2010 - 2011
In Season 4 of the sitcom, Sheldon (Jim Parsons) begins an unorthodox relationship with an equally brilliant—and equally awkward—neuroscientist named Amy Farrah Fowler (Mayim Bialik, who is bumped from recurring cast member to series regular by the end of the season). Meanwhile, Leonard (Johnny Galecki) starts dating a new woman, but there's only one problem: She's Raj's (Kunal Nayyar) sister, and he's not too happy about it. Kaley Cuoco and Simon Helberg also star.
Episode 1
The Robotic Manipulation
Thu, Sep 23, 2010 30 mins
In the fourth-season opener, Sheldon goes on a date with Amy Fowler, his first date ever, and Penny finds herself accompanying them.
Episode 2
The Cruciferous Vegetable Amplification
Thu, Sep 30, 2010 30 mins
Sheldon hatches a plan to extend his lifespan when he realises he won't be around to see the technology that will be able to download his consciousness into a robot.
Episode 3
The Zazzy Substitution
Thu, Oct 7, 2010 30 mins
Everyone worries for Sheldon, who begins searching for non-human companionship.
Episode 4
The Hot Troll Deviation
Thu, Oct 14, 2010 30 mins
Wolowitz is embarrassed when a secret of his is revealed; and Sheldon and Raj battle at work.
Episode 5
The Desperation Emanation
Thu, Oct 21, 2010 30 mins
Sheldon meets Amy's mother and comes to the realisation that he no longer wants to see Amy; and Leonard realises that everyone is in a relationship except for him.
Episode 6
The Irish Pub Formulation
Thu, Oct 28, 2010 30 mins
Raj's sister visits and inadvertently causes trouble for the friends.
Episode 7
The Apology Insufficiency
Thu, Nov 4, 2010 30 mins
Howard baffles Sheldon when he won't accept his apology; and an FBI agent interviews the guys for Howard's security clearance.
Episode 8
The 21-Second Excitation
Thu, Nov 11, 2010 30 mins
The guys camp out in a line hoping to see an anticipated movie, while Penny and Bernadette arrange Amy's first slumber party.
Episode 9
The Boyfriend Complexity
Thu, Nov 18, 2010 30 mins
Penny asks Leonard to lie to her visiting father, while Howard, Raj and Bernadette spend all night looking through a telescope.
Episode 10
The Alien Parasite Hypothesis
Thu, Dec 9, 2010 30 mins
Amy is attracted to Penny's ex-boyfriend; and Raj and Howard argue about which of them would be a better superhero.
Episode 11
The Justice League Recombination
Thu, Dec 16, 2010 30 mins
The guys borrow Penny's new boyfriend when they enter a costume contest as members of the Justice League.
Episode 12
The Bus Pants Utilization
Thu, Jan 6, 2011 30 mins
Leonard has a great idea for a smartphone app, and it causes friction with Sheldon.
Episode 13
The Love Car Displacement
Thu, Jan 20, 2011 30 mins
Howard is jealous when Bernadette runs into her old boyfriend at a science event they're attending.
Episode 14
The Thespian Catalyst
Thu, Feb 3, 2011 30 mins
Sheldon wants acting lessons from Penny, hoping they will make him a better teacher.
Episode 15
The Benefactor Factor
Thu, Feb 10, 2011 30 mins
Leonard has a moral crisis when he meets a wealthy widow who is willing to help the university.
Episode 16
The Cohabitation Formulation
Thu, Feb 17, 2011 30 mins
Howard contemplates a serious decision in his relationship with Bernadette; and Leonard and Raj's sister start seeing each other again.
Episode 17
The Toast Derivation
Thu, Feb 24, 2011 30 mins
Sheldon is in crisis when he realises he's not the epicentre of the group, so, he decides to find new friends.
Episode 18
The Prestidigitation Approximation
Thu, Mar 10, 2011 30 mins
Leonard has a tough choice to make when Priya asks him to stop spending time with Penny, forcing him to choose between the two women; and Howard keeps pestering Sheldon with a magic trick.
Episode 19
The Zarnecki Incursion
Thu, Mar 31, 2011 30 mins
The guys become sleuths to find out who hacked Sheldon's online-game account.
Episode 20
The Herb Garden Germination
Thu, Apr 7, 2011 30 mins
Sheldon and Amy spread gossip as part of an experiment; and Howard and Bernadette's relationship gets serious.
Episode 21
The Agreement Dissection
Thu, Apr 28, 2011 30 mins
Priya uses her legal expertise to rip apart Sheldon's roommate agreement, and the women take the flustered Sheldon out dancing.
Episode 22
The Wildebeest Implementation
Fri, Mar 25, 2011 30 mins
Raj makes an attempt to cure his phobia of talking to women; and Penny spies on Leonard and Priya with the help of Bernadette.
Episode 23
The Engagement Reaction
Thu, May 12, 2011 30 mins
Howard finally tells his mother that he's marrying Bernadette, and the news puts her in the hospital.
Episode 24
The Roommate Transmogrification
Thu, May 19, 2011 30 mins
In the fourth-season finale, Raj moves in with Sheldon when Leonard and Priya's "Star Trek" bedroom fantasy is too much for him; and the guys tease Howard when Bernadette gets her PhD, making Howard the only one without a doctorate.
