ट्रिविया

Paul Naschy died before he completed the dubbing of his character. José Antonio Duque did his voice.

The original story was an idea by Carlos Aured, which was developed by Aured himself and Paul Naschy, the movie main star. Aured was also the director when the shooting began. After a few days, he was fired and replaced by Naschy. The motives of Aured's firing was, in words of the producers, that after more than 20 years without directing, he'd forgotten how to direct a movie. Not long after that, Aured passed away. Although the original story is his, and some sequences of the final cut are some of the ones that he directed, his work as a writer and as a director are uncredited, and only Naschy appears as writer and director.