Directed by Gay Linvill, Nikki Lorre | Starring: Jim Parsons, Kaley Cuoco, Johnny Galecki, Simon Helberg

Physicists Leonard and Sheldon find their nerd-centric social circle with pals Howard and Raj expanding when aspiring actress Penny moves in next door.

The Big Bang Theory - Publicity still of Mayim Bialik & Jim Parsons

More stills and photos from "The Big Bang Theory"