Stone wrote the film adaptation of the train hijacking novel "The Taking of Pelham One Two Three" (1974). He worked on some scripts that were ultimately not produced including "The Leavenworth Irregulars", "The Grand Defiance", and "The Ornament", as well as a musical that was not made, "Subject to Change". He did some uncredited doctoring on the show "Goodtime Charley" (1975) and wrote the TV movie "One of My Wives Is Missing" (1976), a thriller, using the Pierre Marton pseudonym again.