Sat Apr 18 8:00pm
The Plimpton Stimulation(Season 3, Episode 21) TBS

The arrival of a famous physicist (Judy Greer), has Sheldon and Leonard competing for her attention.

Sat Apr 18 8:30pm
The Staircase Implementation(Season 3, Episode 22) TBS

Leonard tells Penny the story of how he met Sheldon.

Sat Apr 18 9:00pm
The Lunar Excitation(Season 3, Episode 23) TBS

In the third-season finale, Wolowitz and Koothrappali play matchmaker for Sheldon by setting up an online-dating profile for him. Meanwhile, Penny thinks that her relationship with Leonard has affected her ability to date "normal" men.

Sat Apr 18 9:30pm
The Robotic Manipulation(Season 4, Episode 1) TBS

In the series four opener, Sheldon goes on a date with Amy Fowler----his first date ever---and Penny finds herself accompanying them.

Sat Apr 18 10:00pm
The Cruciferous Vegetable Amplification(Season 4, Episode 2) TBS

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. Steve Wozniak has a cameo.

Sat Apr 18 10:30pm
The Zazzy Substitution(Season 4, Episode 3) TBS

Everyone worries for Sheldon, who begins searching for non-human companionship.

Sun Apr 19 7:00pm
The Hot Troll Deviation(Season 4, Episode 4) TBS

Wolowitz is embarrassed when a secret of his is revealed; and Sheldon and Raj battle at work.

Sun Apr 19 7:30pm
The Desperation Emanation(Season 4, Episode 5) TBS

Sheldon meets Amy's mother and comes to the realization that he no longer wants to see Amy; and Leonard realizes that everyone is in a relationship except for him.

Sun Apr 19 8:00pm
The Irish Pub Formulation(Season 4, Episode 6) TBS

Raj's sister visits and inadvertently causes trouble for the friends.

Sun Apr 19 8:30pm
The Apology Insufficiency(Season 4, Episode 7) TBS

Howard baffles Sheldon when he won't accept his apology; and an FBI agent (Eliza Dushku) interviews the guys for Howard's security clearance.

Sun Apr 19 9:00pm
The 21-Second Excitation(Season 4, Episode 8) TBS

The guys camp out in a line hoping to see an anticipated movie, while Penny and Bernadette arrange Amy's first slumber party. Wil Wheaton has a cameo.

Sun Apr 19 9:30pm
The Boyfriend Complexity(Season 4, Episode 9) TBS

Penny asks Leonard to lie to her visiting father (Keith Carradine), while Howard, Raj and Bernadette spend all night looking through a telescope.

Sun Apr 19 10:00pm
The Alien Parasite Hypothesis(Season 4, Episode 10) TBS

Amy is attracted to Penny's ex-boyfriend; and Raj and Howard argue about which of them would be a better superhero.

Sun Apr 19 10:30pm
The Justice League Recombination(Season 4, Episode 11) TBS

The guys borrow Penny's new boyfriend when they enter a costume contest as members of the Justice League.

Mon Apr 20 10:00pm
The Bus Pants Utilization(Season 4, Episode 12) TBS

Leonard has a great idea for a smartphone app, and it causes friction with Sheldon.

Mon Apr 20 10:30pm
The Love Car Displacement(Season 4, Episode 13) TBS

Howard is jealous when Bernadette runs into her old boyfriend at a science event they're attending.

Tue Apr 21 8:00pm
The Thespian Catalyst(Season 4, Episode 14) TBS

Sheldon wants acting lessons from Penny, hoping they will make him a better teacher.

Tue Apr 21 8:30pm
The Benefactor Factor(Season 4, Episode 15) TBS

Leonard has a moral crisis when he meets a wealthy widow who is willing to help the university.

Tue Apr 21 9:00pm
The Cohabitation Formulation(Season 4, Episode 16) TBS

Howard contemplates a serious decision in his relationship with Bernadette; and Leonard and Raj's sister start seeing each other again.

Tue Apr 21 9:30pm
The Toast Derivation(Season 4, Episode 17) TBS

Sheldon is in crisis when he realizes he's not the epicenter of the group, so, he decides to find new friends.

Tue Apr 21 10:30pm
The Prestidigitation Approximation(Season 4, Episode 18) TBS

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.

Wed Apr 22 8:30pm
The Zarnecki Incursion(Season 4, Episode 19) TBS

The guys become sleuths to find out who hacked Sheldon's online-game account.

Wed Apr 22 9:00pm
The Herb Garden Germination(Season 4, Episode 20) TBS

Sheldon and Amy spread gossip as part of an experiment; and Howard and Bernadette's relationship gets serious. Physicist Brian Greene has a cameo.

Wed Apr 22 9:30pm
The Agreement Dissection(Season 4, Episode 21) TBS

Priya uses her legal expertise to rip apart Sheldon's roommate agreement, and the women take the flustered Sheldon out dancing.

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  • Premiered: September 24, 2007
  • Rating: TV-PG
  • User Rating:4.58 out of 5 (8,996 ratings)
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  • Premise: Two nerdy physicists share an apartment and an unlikely friendship with their beautiful neighbor with whom one of them is infatuated. Like the universe after the big bang, the show's popularity expanded, thanks to breakout star Jim Parsons, along with the… (more)

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