George Zucco was hired for the part of the Ape Man and showed up for initial costume fittings and preliminary make-up applications, but he fell ill prior to shooting and was replaced by Frank Moran. However, his contract required that he receive third billing, so even though he appears in the film for only a few seconds*, he is still billed third. He does appear in some lobby cards, however, and there are publicity photos taken of him in full costume and make-up. (*Keen eyed viewers will spot him in the initial scenes of the dormant ape-man lying on Dexter's lab table. Frank Moran takes over just as creature stirs and wakes up). He did recover to join Bela Lugosi and John Carradine in the follow-up, "Voodoo Man."
Most of the "Arctic expedition" footage is taken from a 1926 Pathe two-reeler, Alaskan Adventures.