Black Friday

University professor George Kingsley is struck by gangsters while crossing the street, leaving him with brain damage and one of the gangsters, Cannon, paralyzed. Kingsley's friend Dr. Sovac attends to both men, and when Cannon offers him a reward for aiding his recovery, Kovac transplants part of Cannon's brain into the dying Kingsley's skull, creating a dual personality.

Directed by Arthur Lubin, Black Friday leans on a strong ensemble — Stanley Ridges, Boris Karloff, Bela Lugosi — to carry a story that balances spectacle with character.

The film landed with audiences for its craft and performances, and remains one of the most talked-about science fiction titles of 1940.