Plimpton also appeared in a number of feature films as an extra and in cameo appearances. He had a small role in the Oscar-winning film "Good Will Hunting", playing a psychologist. Plimpton played Tom Hanks's antagonistic father in "Volunteers". He was also notable for his appearance in television commercials during the early 1980s, including a memorable campaign for Mattel's Intellivision. In this campaign, Plimpton aggressively touted the superiority of Intellivision video games over those of competitors such as the Atari 2600.