A popular nightclub performer, Charles Knapp occasionally accepted character roles in feature films. He became a New York stage actor shortly after WWII's end. In 1948, he moved West to launch a film career and made his debut in J.W. Coop (1971). Subsequent film appearances include Chinatown (1974), Mother, Jugs & Speed (1976), The Frisco Kid (1979), and Blade Runner (1982). The portly actor frequently played officious types.