The Ghost of Frankenstein

When Ygor (Lugosi) brings the monster (Chaney) to Dr. Ludwig Frankenstein's (Hardwicke) castle, he decides that a brain transplant might be in order. While Dr. Frankenstein thinks the transplant should be of a healthy and sane brain, Ygor plots with Frankenstein's unscrupulous colleague Dr. Bohmer (Lionel Atwill) to transplant Ygor's brain instead so that he can rule the world using the monster's body. Their plan turns sour when the monster becomes malevolent and goes on a rampage in the nearest town.