Trapper John, M.D. is an American television medical drama and spin-off of the film MASH. Pernell Roberts portrayed the title character, a lovable surgeon who became a mentor and father figure in San Francisco, California. The show ran on CBS from September 23, 1979, to September 4, 1986. Roberts played the character more than twice as long as had Wayne Rogers (1972-1975) in the series M*A*S*H.