Dev-Em was a juvenile delinquent on the planet Krypton who became imprisoned in the Phantom Zone. Eventually he escaped during the 30th Century, where he turned over and became a teenage super-hero. He has been a member of the Interstellar Counter-Intelligence Corps and the Legion of Super-Heroes. Dev-Em was created by Jerry Siegel and George Papp, first appearing in Adventure Comics #287. (1961)