The Big Bang Theory: 10 Characters You Totally Forgot Existed

Season 3, Episode 21: The Plimpton Stimulation

When Sheldon learns Dr Elizabeth Plimpton is being considered for a position in Caltech, he lets her stay at his place before her meeting. Being a cosmological physicist, a Princeton graduate, and an author on quantum cosmology, it feels like Plimpton will fit in perfectly at the university.

But since Plimpton is a raging nymphomaniac, she's more interested in sleeping with Leonard. And Howard. And Raj. And Sheldon... at the same time. She is so sex-crazed, she claims she wrote her first book nude. (She was nice enough to demonstrates this by reciting her work verbatim while stark naked in front of Leonard.) Judy Greer, who plays Plimpton, often plays timid and reserved characters so it's surreal to see her playing someone trying to seduce anyone with a pulse.

Being a horny Slutbunny (as Penny gracefully calls her), you'd think Plimpton would be one character you would have no problem remembering. But since she appeared in an early episode and the show is teeming with larger-than-life eccentrics, she's not as memorable as she should be.