Deep in the jungle, plantation manager Barney Chavez, (Raymond Burr, best known as TV''s Perry Mason) kills his elderly employer to get to his beautiful wife (Barbara Payton). However, an old native witch witnesses the crime & puts a curse on Barney, who soon finds himself turning into a rampaging gorilla nightly...Or is it just in his head? The Police Commissioner (Lon Chaney) wants to find out!