Joyce Meadows said she had no idea this film had developed a cult following until 1985 when she was invited to be a guest at an autograph show. She called a service in New York to order photos to sign and the guy working there said they had a lobby poster of this movie if she wanted to buy it. When he told her it was $650, she was shocked and told him, "My god, the movie didn't even cost that much to make!"
The special eye effects for Steve March were created by having John Agar wear special black contact lenses that were very thick. The extreme thickness of the contact made it painful for Agar to wear them.
Dan is reading "Space Science Fiction" Vol.1 No.2 August 1957 issue. Part of the cover showing the word "Space" is ripped off. Boris Karloff can be seen on the back cover.
Director Nathan Juran insisted on being billed as "Nathan Hertz" (Hertz was Juran's middle name), apparently because he was embarrassed by this film's low budget and poor quality.