Geeks and jocks have different ideas on the meaning of the "Big Bang" theory.

Leonard hangs out with Penny's friends but ultimately has no interest in football

Howard tries to make amends with Raj

Leonard discovers that Penny hides him from her friends

Sheldon teaches Leonard about football so he can fit in with Penny's friends

Leonard learns about football from an unlikely tutor, on "The Big Bang...

Sheldon finally has a chance to destroy the man who crushed his dreams

Howard and his date bond over their controlling mothers

Sheldon agrees to play in the card game tournament to get revenge on a player

Howard and Leonard made a pact to set the other person up