The Big Bang Theory - Season 4, Episode 17: The Toast Derivation

The Big Bang Theory - Season 4, Episode 17: The Toast Derivation
Channel: CBS
Air Date: 24/Feb/11

Leonard (Johnny Galecki) and Priya (Aarti Mann) are now openly dating making the gang hangout more at Raj's (Kunal Nayyar) place making Sheldon (Jim Parsons) a bit concerned. Taking matters into his own hands Sheldon decides to create a new group consisting of Kripke (John Ross Bowie), Zack (Brian Smith) and Stuart (Kevin Sussman) while Leonard, Raj and Wolowitz (Simon Helberg) realize that they miss Sheldon's antics. LeVar Burton guest stars as himself.

The Big Bang Theory - Season 4, Episode 14: The Thespian Catalyst

The Big Bang Theory - Season 4, Episode 14: The Thespian Catalyst
Channel: CBS
Air Date: 3 February 2011

Sheldon (Jim Parsons) feeling that he did a good job as an instructor was enlighted when he read some of the students tweets. Feeling bad about his lack of talent in teaching he asks Penny (Kaley Cuoco) for acting lessons meanwhile Raj (Kunal Nayyar) has been having impure thoughts about Howard's (Simon Helberg) girlfriend Bernadette (Melissa Rauch).

The Big Bang Theory - Season 4, Episode 12: The Bus Pants Utilization

The Big Bang Theory - Season 4, Episode 12: The Bus Pants Utilization
Channel: CBS
Air Date: 6 January 2011

Leonard (Johnny Galecki) gets an idea for a great new app and pitches it to the guys. Everyone gets psyched working on the project but Sheldon (Jim Parsons) being himself wears down the guys and gets him ejected from the project.

The Big Bang Theory - Season 4, Episode 11: The Justice League Recombination

The Big Bang Theory - Season 4, Episode 11: The Justice League Recombination
Channel: CBS
Air Date: 16 December 2010

Penny (Kaley Cuoco) gets pissed at Leonard (Johnny Galecki) and the guys for making fun of his boyfriend Zack, so they decide to apologize and end up inviting him to a costume party at the comicbook store on New Year's eve. They ask Zack to be Superman and he quickly agrees but it's Penny that they may need a lot of convincing to do before she agrees to be Wonderwoman. Brian Thomas Smith reprises his role as Penny's boyfriend Zack.

The Big Bang Theory - Season 4, Episode 10: The Alien Parasite Hypothesis

The Big Bang Theory - Season 4, Episode 10: The Alien Parasite Hypothesis
Channel: CBS
Air Date: 9 December 2010

While having dinner with Penny (Kaley Cuoco) and Bernadette (Melissa Rauch), Amy (Mayim Bialik) see's Penny's ex and it makes her feel something that she has never felt before. Sheldon (Jim Parsons) on the other hand try and help to figure out what this new emotion Amy (Mayim Bialik) is feeling. Raj (Kunal Nayyar) and Wolowitz (Simon Helberg) on the other square off to prove who is the real superhero and who is the sidekick.

The Big Bang Theory - Season 4, Episode 8: The 21-Second Excitation

While waiting in line to watch the extended version of an Indiana Jones movie Sheldon (Jim Parsons), Howard (Simon Helberg), Leonard (Johnny Galecki) and Raj (Kunal Nayyar) have another unpleasant encounter with Will Wheaton. All the while Penny (Kaley Cuoco), Bernadette (Melissa Rauch) and Amy (Mayim Bialik) try to have fun on their girls night out.

Channel: CBS
Air Date: 11 November 2010