Professor Chang is a real life doctor!

Before Community's Ken Jeong was on TV and film, he was practicing medicine. Now, The Hangover Part II star, 42, is combining his medical training with his comedic prowess in a Hands-Only CPR Video from the American Heart Association.

The PSA uses the disco hit "Stayin' Alive" to help people remember what to do in a sudden cardiac arrest emergency.

"I may play insanely crazy and comedic characters on screen, but as an internal medicine physician in real life, I want people to know that sudden cardiac emergency is a serious matter," Jeong tells Us Weekly. "Immediate action can be the difference between life and death. Everyone needs to know it’s in their hands to help save a life." 

The American Heart Association is working with, an innovative social fundraising website founded by actor Edward Norton, to raise money to support the association's lifesaving research and educational programs. In the video, one of Jeong's friends collapses during a game of charades; fortunately, he dances around and instructs his pals how to perform Hands-Only CPR using the beat of the Bee Gees' "Stayin' Alive."

Watch the video above.