The Big Bang Theory is centered on five characters living in Pasadena, California: roommates Leonard Hofstadter and Sheldon Cooper; Penny, a waitress and aspiring actress who lives across the hall; and Leonard and Sheldon's equally geeky and socially awkward friends and co-workers, mechanical engineer Howard Wolowitz and astrophysicist Raj Koothrappali. The geekiness and intellect of the four guys is contrasted for comic effect with Penny's social skills and common sense.Whether on or above Earth, hilarity is outrageously universal in TV's most popular comedy featuring four forward-thinking but socially backward geniuses. Fun discoveries multiply: Leonard learns jealousy is bad for a relationship (with Penny) but science is good for seduction (of Penny). Howard finds life in the International Space Station life is no escape from terrestrial turmoil between his mom and his new wife Bernadette. Raj meets someone special who may be a good match, if he can keep her from fleeing mid-date. And then there's Sheldon. He learns what not to say after facing harassment charges or competing for tenure at work and how Dungeons & Dragons can be the icebreaker his relationship with Amy needs.