
Mensa-fied best friends and roommates Leonard and Sheldon, physicists who work at the California Institute of Technology, may be able to tell everybody more than they want to know about quantum physics, but getting through most basic social situations, especially ones involving women, totally baffles them. How lucky, then, that babe-alicious waitress/aspiring actress Penny moves in next door. Frequently seen hanging out with Leonard and Sheldon are friends and fellow Caltech scientists Wolowitz and Koothrappali. Will worlds collide? Does Einstein theorize in the woods?

Leonard volunteers to sign for a package, hoping to make a good impression on Penny.

Unhappy to learn that Penny is seeing someone, Leonard summons the courage to ask another woman on a date.

While facing dramatic changes in his relationship with Amy, Sheldon pushes Penny and Leonard to choose a wedding date.

Sheldon struggles to understand what is going on with Amy; Penny must decide if she can get past Leonard's bad behavior.