Mr. Chameleon is a detective fiction radio drama created by Frank Hummert and produced by Frank and Anne Hummert. It ran on CBS Radio from July 14, 1948, to 1951 or 1953. The series starred Karl Swenson as a New York police detective who is a master of disguise, and who assumes a new identity in each episode in order to catch a criminal. The listening audience is always aware of who Mr. Chameleon is, no matter in which disguise he appears. According to the series' opening voice-over, "Chameleon" is not a nickname or pseudonym but the character's actual surname, one which he has tried to live up to since childhood. His motto is, "The innocent must be protected and the guilty must be punished." The theme song is John Jacob Loeb and Paul Francis Webster's "Masquerade".