Mazursky began his film career as an actor in Stanley Kubrick's first feature, "Fear and Desire" (1953). Kubrick asked for verification of his name for the credits and at that point he decided on a first-name change to Paul. Two years later he appeared in a featured position as one of a classroom of teenagers with issues towards authority in "The Blackboard Jungle" (1955). His acting career continued for several decades, starting with parts in episodes of television series such as "The Twilight Zone" and "The Rifleman".