The Big Bang Theory - 4x21 - The Agreement Dissection

Episode Summary : Sheldon goes dancing with the girls while Priya tries to break down the roommate agreement using legal theory.

[Runtime : ~22'] - [Orig. Air Date: 28 Apr 2011]

The Big Bang Theory - 4x20 - The Herb Garden Germination

Episode Summary : 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.

[Runtime : ~22'] - [Orig. Air Date: 07 Apr 2011]

The Big Bang Theory - 4x19 - The Zarnecki Incursion

Episode Summary : When Sheldon has his online gaming account hacked and his character stolen from, the guys team up to discover out who did it.

[Runtime : ~22'] - [Orig. Air Date: 31 Mar 2011]

The Big Bang Theory - 4x18 - The Prestidigitation Approximation

Episode Summary : Sheldon is baffled by Wolowitz's magic trick. Meanwhile, Leonard realizes dating Priya may make it impossible to continue being friends with Penny.

[Runtime : ~22'] - [Orig. Air Date: 10 Mar 2011]

The Big Bang Theory - 4x17 - The Toast Derivation

Episode Summary : Realizing Leonard is the center of the gang, Sheldon seeks to form a new group of friends of which he can be the center.

[Runtime : ~22'] - [Orig. Air Date: 24 Feb 2011]

The Big Bang Theory - 4x16 - The Cohabitation Formulation

Episode Summary : Wolowitz finds himself having to choose between Bernadette and his mother. Leonard has another rendezvous with Raj's sister Priya.

[Runtime : ~22'] - [Orig. Air Date: 17 Feb 2011]

The Big Bang Theory - 4x15 - The Benefactor Factor

Episode Summary : An aged, but wealthy, Caltech donor wants sex from Leonard in exchange for another large donation.

[Runtime : ~22'] - [Orig. Air Date: 10 Feb 2011]

The Big Bang Theory - 4x14 - The Thespian Catalyst

Episode Summary : Hoping it will make him a better teacher, Sheldon has Penny give him acting lessons. Raj has fantasies about a friend's girlfriend.

[Runtime : ~22'] - [Orig. Air Date: 03 Feb 2011]

The Big Bang Theory - 4x13 - The Love Car Displacement

Episode Summary : A science convention at a hotel leads to Bernadette running into an ex-boyfriend and Wolowitz worrying he can't quite compare.

[Runtime : ~22'] - [Orig. Air Date: 20 Jan 2011]

The Big Bang Theory - 4x12 - The Bus Pants Utilization

Episode Summary : Leonard's friendship with Sheldon becomes strained when they both fight over an idea for a smartphone application.

[Runtime : ~22'] - [Orig. Air Date: 06 Jan 2011]

The Big Bang Theory - 4x11 - The Justice League Recombination

Episode Summary : The guys rope Zack into their costume contest entry as the Justice League.

[Runtime : ~22'] - [Orig. Air Date: 16 Dec 2010]

The Big Bang Theory - 4x10 - The Alien Parasite Hypothesis

Episode Summary : Amy crushes on one of Penny's dim ex-boyfriends. Raj and Wolowitz argue over who'd be the better superhero.

[Runtime : ~22'] - [Orig. Air Date: 09 Dec 2010]

The Big Bang Theory - 4x09 - The Boyfriend Complexity

Episode Summary : When Penny's father visits, she gets Leonard to pretend to still be her boyfriend. Meanwhile, Howard, Raj, and Bernadette spend the night on an astronomy project. [source: tv.com]

[Runtime : 20:33] - [Orig. Air Date: 18 Nov 2010]