According to Mary Louise Weller, the people working on the film had to deal with uncomfortably hot temperatures (115-125 degrees), lack of shade, lack of water, lack of electricity, and lack of screens to keep out swarming insects. There was only one small restaurant in the local area. People making the movie attempted to stay cool by sitting in the ocean.
Mary Louise Weller said on a Cult Film Freak interview upon the question of acting in a monster movie: "It wasn't scripted to be about any monsters, but since it was actually blocked currency from numerous countries... Mexico, UK, Greece, USA... they used the movie as a way to move cash around. It was just amazing that it even cut together at all."
This film is part of a string of low budget horror movies starring José Ferrer that includes Crash (1976), La sentinelle des maudits (1977), Zoltan, le chien sanglant de Dracula (1977), Les tueurs de l'éclipse (1981), and The Being (1981).
The film was released on Arrow Video Blu Ray with two-sided covers. It includes the original cover of Deborah Shelton with the forehead marking in black and white with the title in bright red, and a new painted cover showing Shelton (Madeline Grice), James Earl Jones (Frye), and Lila Kedrova (Sister Anna).