
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?

Wolowitz questions his engineering skills after he and Sheldon can't get a toy drone to fly; a canceled flight puts Leonard's plans in jeopardy; Raj sets his parents against one another after he's cut off financially.

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

When Sheldon's and Leonard's mothers finally meet, personalities collide; Howard decides to do his share of the chores -- with a little help from his friends.

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.