When the apartment opens up above Leonard and Sheldon, Wolowitz decides it's time to leave his mother's house and move in.   However, after getting into a fight with his mother, he ends up not taking the apartment and instead a beautiful girl, Alicia (Valerie Azlynn) moves in.  Alicia, it turns out, is also an actress but much more successful than Penny having already been in national commercials and on soap operas.

Wolowitz, Raj and Leonard instantly fall for Alicia and help her move and set up her stereo.  Penny even tries dressing up in a little dress but it still ignored by the guys who are obsessed with Alicia.  Penny brings Chinese for the guys and even completes all of Sheldon's ridiculous requests, but is ditched when Alicia comes in and need a ride to her CSI audition, which she, of course, gets.

Penny finally calls Alicia out for be a user when they meet in the laundry room.  Alicia then asks how it's any different than what Penny does.  Penny definitely does use, but at least in this episode we see she's becoming more on their level as she makes a nerdy star trek reference in her conversation with Alicia.

Outside in the hallway, the girls get into a catfight as the boys watch.  At the end of the episode, Penny and guys are sitting in their apartment and they overhear Alicia sleeping with the CSI producer.

The episode title come from the role Alicia was auditioning for on CSI, a dead hooker.