 Born in Rome, Gemma first worked as a stuntman, then was offered real acting parts by director Duccio Tessari, starting with the film "Arrivano i titani" (1962).He also made an appearance in Luchino Visconti's "Il Gattopardo" as Garibaldi's General.Gemma later went on to star in spaghetti westerns in films such as "A Pistol for Ringo" ("Una pistola per Ringo"), "Blood for a Silver Dollar" ("Un dollaro bucato"), "Wanted" and "Day of Anger" ("I giorni dell'ira").