Ken Jeong stars in the NBC show "Community", but most people know him as the doctor in "Knocked Up", or the Asian gangster 'Mr. Chow" in the "Hangover" movies. But before he was an actor, he really was a doctor. And now he's in a video for the American Heart Association that teaches people to do CPR to the beat of the Bee Gees song, "Stayin' Alive".