Dana Carvey gained fame during his time on "Saturday Night Live" for his impressions, whether he was imitating former President George H. W. Bush or lampooning news anchor Tom Brokaw. Now, he's using his mimicking skills to mentor others in his role as expert-in-residence for this competition that pits amateur impressionists against one another. A winner is crowned each week as the contestants put their abilities to the test in a variety of challenges. Celebrities -- including actor Steve Carell, former late-night mainstay Jay Leno and actress Kate Flannery -- coach the challengers. Actor Freddie Prinze Jr. hosts.