In a remote South American rubber plantation, overseer Barney Chavez kills his employer, Klaas Van Gelder. Witnessed by a local native witch/maid, Barney is placed under a voodoo curse. He marries his boss's widow, Dina Van Gelder, but begins transforming nightly into a demon gorilla. Police Commissioner Taro and local physician Dr. Viet investigate a series of animal killings and close in on Barney.
| Actor | Role |
|---|---|
 Raymond BurrBarney Chavez | Barney Chavez |
 Barbara PaytonDina Van Gleder | Dina Van Gleder |
 Lon Chaney Jr.Commissioner Taro | Commissioner Taro |
 Tom ConwayDr. Viet | Dr. Viet |
 Paul CavanaghKlaas Van Gelder | Klaas Van Gelder |
| GGisela WerbisekAl-Long | Al-Long |
 Carol VargaLarina | Larina |
 Paul MaxeyVan Heusen | Van Heusen |
 Woody StrodeNedo | Nedo |
 Martín GarralagaNative | Native |
| FFelippa RockStella Van Heusen | Stella Van Heusen |
 Moyna MacGillMme. Van Heusen | Mme. Van Heusen |
| SSteve CalvertGorilla (uncredited) | Gorilla (uncredited) |
| AArt FelixNative (uncredited) | Native (uncredited) |
| AAugie GomezNative (uncredited) | Native (uncredited) |
| TTony UrchelNative (uncredited) | Native (uncredited) |