Ryan Lee Stiles is an American-Canadian actor, comedian, and producer whose work is often associated with improvisational comedy. He is best known for his work on Whose Line Is It Anyway?, both the original British version and the subsequent American version, and for his role as Lewis Kiniski on The Drew Carey Show. He also played Herb Melnick on the CBS comedy Two and a Half Men and was a performer on the show Drew Carey's Improv-A-Ganza.

Whose Line Is It Anyway? is an American improvisational comedy television series, and is an adaptation of the British series of the same name. It originally aired on ABC and ABC Family from August 5, 1998 to December 15, 2007, hosted by Drew Carey. A revival of the show, hosted by Aisha Tyler, began airing on The CW on July 16, 2013.