The Big Bang Theory's lead stars, Kaley Cuoco and Johnny Galecki, reunite on-screen in a promotional video for a mobile game.

From Kaley Cuoco and Johnny Galecki's relationship to saying goodbye to the show, here are the biggest takeaways from The Big Bang Theory ... have their characters Leonard and Penny also part ...

But Her Reason Actually Makes Sense Stuart Bloom was introduced in The Big Bang Theory Season 2 episode “The Hofstadter Isotope” as the owner of the comic book store that Leonard, Sheldon ...

This Big Bang Theory episode is filled with Sheldon's signature physical comedy and the gang's lack of social skills. When Penny gifts Sheldon a napkin used and autographed by actor Leonard Nimoy ...