The Big Bang Theory - The Roommate Agreement

Sheldon and Leonard sneak into Penny's apartment to clean and organize it while she's sleeping, leading to a confrontation when Penny discovers their intrusion. Penny expresses her discomfort and revokes Leonard's key.

Penny retaliates by taking Leonard's laundry, prompting Sheldon to escalate the conflict by moving Penny's underwear to a telephone wire. This leads to a series of escalating pranks.

The conflict between Sheldon and Penny prompts Sheldon to call his mother who scolds him. Sheldon relents and returns Penny's laundry and rescinds her laundry 'strikes'.

Leonard's new relationship is jeopardized when Sheldon alters Leonard's Facebook relationship status as the battle between Sheldon and Penny moves onto Leonard's love life. Leonard expresses his anger at Sheldon's interference.

Howard and Leonard confront Sheldon about his past behaviors. These come in the form of past betrayals and inconsiderate actions. An uneasy truce forms between the group with the exception that Sheldon using Leonard's tooth brush is unforgivable.

Leonard refuses to sign Sheldon's updated roommate agreement. Sheldon activates a 'self destruct' to email Leonard's parents about his secret relationship to a white person. Leonard relents and signs the roommate agreement under duress.

Sheldon spoils a major plot point in one of the Harry Potter books. Leonard gets angry at Sheldon's inconsiderate action which escalates into Sheldon and Leonard fighting.

Leonard refuses to return a DVD to the video store. Sheldon insists. Leonard takes multiple absurd actions to try and get out of returning the video. Ultimately, Sheldon reveals that the DVD was never late.

Sheldon rents out his recently vacated room to a stranger, Theodore, without Leonard's consent, creating further tension in the apartment. Penny and Leonard are angered by this inconsiderate act.

Sheldon and Leonard are fighting because of relationship issues. Penny points out that they should face their feelings as housemates and friends. Sheldon and Leonard apologize and make a show of bonding.