Due to Hall's height, he was often cast in Monster roles. He made his acting debut in the 1979 horror film Prophecy. He appeared as the alien in the 1980 horror film Without Warning and as Gorvil in the 1982 television movie Mazes and Monsters. In 1985, he co-starred in the short-lived series Misfits of Science. He guest-starred on the sitcom Night Court as a huge but gentle mental patient who humorously towered over bailiff Bull Shannon, played by Richard Moll, who is 6 ft 8 in (2.03 m), and a fellow mental patient, played by James Cromwell, who is 6 ft 7 in (2.01 m). The next year, Hall portrayed yet another Monster in the horror film Monster in the Closet, followed by the role of Harry in Harry and the Hendersons.