
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?

When competitors Pemberton and Campbell charm America on a publicity tour, Sheldon and Amy try to win over Nobel laureates Kip Thorne, George Smoot and Frances Arnold; Halley's fear of the dark leads to opportunity and conflict.

Raj faces deportation if he does not find a job; Leonard and Penny deal with Howard as a third wheel.

Sheldon and Amy build a blanket fort -- and come to a crossroads in their relationship; Wolowitz meets a half-brother he didn't know he had; Leonard and Penny have an argument during an appearance on Wil Wheaton's podcast.

The guys fight over what message Raj should write for NASA in case of alien contact; Penny has to decide between auditioning for a movie or keeping her pharmaceutical sales job.