In a published interview, writer Russ Jones related that director of photography Austin McKinney was struck on the head by a large piece of set lumber and knocked unconscious. Upon regaining consciousness, he continued working despite a bleeding head wound.
Writer/producer Russ Jones did double duty as an actor, due to the unexpected absence of the one that didn't show up: as the Londoner killed by the mob in "King Vampire," and the resurrected corpse of Charles in "Monster Raid," even doing his own gruesome makeup.
The uncredited actress playing Miss Clark, the secretary in "King Vampire" was then married to co-star Ron Doyle.
Director David L. Hewitt cribbed much of the music from the 1960 Allied Artists release THE HYPNOTIC EYE.