Sergio Leone was an Italian film director, best known for his work in the Spaghetti Western genre. He directed some of the most influential films of the 1960s and 1970s, including 'A Fistful of Dollars' (1964), 'For a Few Dollars More' (1965), and 'The Good, the Bad and the Ugly' (1966). Leone's films are characterized by their epic scope, dark humor, and moral ambiguity. He is widely considered to be one of the greatest directors of all time.