The original director, Antonio Román, was fired by producer Fulvio Lucisano for his slow pace and not meeting the standards after directing less than 10% of the film. Although Mario Bava directed the bulk of the movie, he is not credited at all for directing it.
This film and its poster are inspiration for the parody film "Nebraska Jim" in Tarantino's "Once Upon a time in Hollywood "
Italian censorship visa # 46675 delivered on 18 March 1966.