The Walking Dead (1936)

Boris Karloff stars in this classic horror film as John Elman, a man who comes back from the dead to seek revenge on the gangsters who framed him for the murder of the judge who first jailed him. After evidence proving Elman's innocence arrives seconds following his electrocution, officials allow Dr. Evan Beaumont (Edmund Gwenn) to experiment with putting a mechanical heart into Elman. The device revives the dead man, but he has become a monstrous, white-haired, vengeful zombie. Directed by Oscar winner Michael Curtiz, this thriller is a must-have for fans of the genre.