The Big Bang Theory made science funny without trying too hard. It gave us a bunch of oddball geniuses who argued about string theory one minute and wore superhero costumes the next.

Kaley Cuoco and Johnny Galecki reunite in a surprise commercial that marks their first on-screen moment together in years.

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