Seven Guest Stars Who Blew Our Minds on The Big Bang Theory

Charlie Sheen! Stan Lee! Bill Nye! Watch our favorite surprise celeb moments from the series

STAN LEE

Sheldon meets another one of his icons in episode 16 of season 3 when he tags along with Penny (Kaley Cuoco) and shows up at the home of Lee, the former Marvel Comics editor in chief and creator of many of the biggest superhero franchises. Needless to say, Lee is not happy about it.