The Big Bang Theory Season 4 Episode 22
The Wildebeest Implementation
Penny, Amy and Bernadette go shopping together. Bernadette mentions that she was invited to dinner with Howard, Leonard and Priya. Amy decides that Bernadette should be a spy for Penny.
At dinner, Bernadette tells a tale about Penny going overseas to film a movie and Leonard wonders why she didn't tell him. Of course, Priya gets upset. It only gets worse, when Leonard is jealous when Bernadette says Penny is also dating an astronaut. Bernadette asks Priya about her trip with Leonard to India and whether they were getting engaged. Bernadette tries to go to the bathroom again to report back on the news, but she cracks under Priya's questioning and rushes out of the apartment.
Sheldon spends the episode creating a three-person chess game. Instead he designs a weird combination of chess and a role-playing game of sorts.
Raj leaves his apartment for his sister's dinner party and goes to Sheldon's apartment. He arrives depressed, lonely and with a decision to make. He was offered an experimental drug that would help him talk to girl's without being drunk. Sheldon tells him to take them and they head out to a coffee shop. The pills work, Raj was able to talk to a girl, but all inhibitions were removed. He ends up stripping in the coffee shop.
In the end, Sheldon, Leonard, and Raj play Sheldon's new complicated game, while Raj watches from the kitchen -- naked.