Christmas carol

Courtesy Dad's Garage

Fans of the improv comedy show "Whose Line Is It Anyway?" probably know Colin Mochrie as one of the original cast members. He's been on the U.S. version for 20 years and appeared in the British show before that. 

The iconic comedian will perform at Dad's Garage in Atlanta this weekend. Mochrie chatted with "On Second Thought" host Virginia Prescott about his upcoming performance and the rules of improv comedy.