Chaney plays two roles: mad scientist Arthur Lamb and Lamb's "experiment", known only as the Ape Man. This hideous creature was the result of Lamb's attempts to transplant animal glands into human beings.
| Directing | Wallace Worsley | Director |
| Editing | Paul Bern | Editor |
| Directing | James Dugan | Assistant Director |
| Writing | Barry Pain | Story |
| Production | Samuel Goldwyn | Producer |
| Art | Cedric Gibbons | Art Direction |
| Writing | J.G. Hawks | Writer |
| Camera | Norbert Brodine | Director of Photography |
