Campanella's first film role was as Mook, the Moon-Man in the 1949 science-fiction series Captain Video and His Video Rangers and went on to appear in more than 100 film and television episodes, usually playing the "tough guy". Campanella appeared as a bartender in Mel Brooks' The Producers (1967), starring Zero Mostel and Gene Wilder, and his many film credits included roles in What's So Bad About Feeling Good? (1968), The Gang That Couldn't Shoot Straight (1971), The Stone Killer (1973), Capone (1975, as Big Jim Colosimo), Chesty Anderson, USN (1976), Heaven Can Wait (1978), The North Avenue Irregulars (1979), High Noon, Part II: The Return of Will Kane (1980), Death Wish II (1982), Young Doctors in Love (1982), The Flamingo Kid (1984), Nothing in Common (1986), Overboard (1987), Beaches (1988), Blood Red (1989), Pretty Woman (1990) and Dick Tracy (1990). He helped Robert De Niro learn Sicilian for his role as young Vito Corleone in Francis Ford Coppola's The Godfather: Part II (1974).