Written, directed and produced by Robert Clarke — the only movie he’d write and direct, sadly, after a career of acting in movies like The Astounding She-Monster — this movie was inspired by the success of that film. After all, Clarke got five percent of She-Monster’s profits in addition to his salary. Although Clarke later admitted that the film was awful, it was a financial success for him and enabled this movie to happen.
With a crew that was made up of University of Southern California film students and a cast of friends and unknowns, this movie was made over twelve weekends with three cinematographers.
An unauthorized sequel, Don Glut’s Wrath of the Sun Demon (which features the real Sun Demon mask from Bob Burns’ collection) was produced in 1965. Two redubbed versions of the original film havealso been released: Hideous Sun Demon: Special Edition and What’s Up, Hideous Sun Demon (AKA Revenge of the Sun Demon), the latter of which had Clarke’s blessing. Both Susan Tyrel and Jay Leno were involved with that movie.
Perhaps the most interesting thing about this film is the claim that its amongst the first movies to use practical locations, which is common practice today.
Dr. Gilbert “Gil” McKenna (Clarke) falls unconscious after accidentally being exposed to radiation yet he has no burns nor damage to his body. However, when he’s in the sun, he transforms into a prehistoric reptile man, destroying all notions of both scientific evolution and religious Creationism.
Once he realizes that he can never go into the sun again, he does what you or I would do. He drinks himself blind drunk and gets involved with a girl at a bar and battles some toughs over her.
In the scene where the radio announcer is warning the public that the Sun Demon is loose, he then says, “I return to music by the King Sister.” Clarke was married to Alyce King of the singing King Sisters and Marilyn King wrote and performed “Strange Pursuit”, the song in the bar scene.
A $50,000 budget, helped by weekend camera rentals which were more affordable, and a $500 rubber suit has never gone so far as it does in this film.