Spencer Milligan is best known for his role as Park Ranger Rick Marshall, the father on the 1970s cult-classic kids' TV show "Land of the Lost." His first role was in the 1973 science fiction comedy by Woody Allen, "Sleeper," in which he played Jeb Hrmthmg, a man Allen's character encounters in the future. After two seasons on "Land of the Lost," Milligan and the producers had a contract dispute regarding merchandising royalties, and he left the show. He was replaced by Ron Harper, who stepped in as Milligan's character's brother, Jack Marshall, for the third and final season.
Throughout the 1970s and early 1980s, Milligan didn't have many starring roles, though he appeared on several different TV shows as a guest star, including "The Bionic Woman," "The Dukes of Hazzard," and "Quincy M.E.." He never again found the success he enjoyed on "Land of the Lost," though, and his last screen credit came in 1987 when he appeared on an episode of the soap opera "General Hospital." Milligan eventually moved to Wisconsin, where he taught acting and directed plays for various local theater groups.