 This is the film that ended the partnership between Lucio Fulci and  Dardano Sacchetti. Fulci claims he came up with the story, Sacchetti  wrote a treatment and they were to make it together, but it  continually fell through. Eventually Sacchetti copyrighted the story  himself and made the film with Lamberto Bava. Sacchetti claims that  the story had been his all along and Fulci was just upset because  the project never took off with him as director.