Sheldon faces a relationship crossroad with Amy when they build a blanket fort on The Big Bang Theory. "The Fortification Implementation" is the 20th episode of the show's eighth season.
The ladies search for a girl for Koothrappali when he joins them on a night on the town on The Big Bang Theory. "The Santa Simulation" is the 11th episode of the show's sixth season.
Penny has a talk with Sheldon, most likely about his new relationship with Ramona and how that could affect things with Amy. Talk some sense into him, Penny!
In nine seasons of The Big Bang Theory, we've never met Leonard's father. Until now! Chaos ensues when he shows up, along with both Leonard's other and Sheldon's.
Sheldon: I'll have a diet Coke. Penny: Can you please order a cocktail? I need to practice mixing drinks. Sheldon: Fine... I'll have a virgin Cuba Libre. Penny: That's... rum and Coke without the rum. Sheldon: Yes, and would you make it diet?
