
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?

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

After their apartment is robbed, Leonard and Sheldon turn to their friends to create a state-of-the-art security system.

Things do not run smoothly when Amy moves in with Sheldon, and Leonard and Penny have to intervene; Howard and Bernadette find unexpected guests at their house when they decide to cancel their vacation plans.

Penny learns there are fans of her performance in "Serial Ape-ist" when she and Leonard attend a Comic Con event; Amy hosts a brunch at Penny's apartment; Wolowitz makes an impulsive purchase.