Bride of the Gorilla
(1951)

Beautiful blonde Dina Van Gelder (Barbara Payton) lives with her rich elderly husband Klaus Van Gelder on his rubber plantation in the jungle. The tough foreman Barney (Raymond Burr) and Dina fall for each other.  Barney throws Klaus to be bitten by a poisonous snake.  Barney and Dina marry and continue to run the plantation.  The old native servant woman saw Barney kill Klaus. She puts a voodoo spell on Barney that makes him turn into a beast at night.  Nearby farms begin to report animals killed at night by a beast.

Local policeman Taro (Lon Chaney Jr) is suspicious of Barney but has no proof.  Barney disappears into the jungle every night, and there are more sightings of the beast.  Dina tries to make Barney move away, but he claims the jungle is calling him.  The local doctor thinks it is all in Barney's head, with the suggestion he has been cursed is making him act like this.

Barney goes into the jungle again, and Dina follows him.  When Taro and the doctor find out, they get guns and go after Dina.  They see Dina being attacked by a gorilla.  They shoot the gorilla, and it turns back into Barney as it dies.

Thanks Joseph C!