The Brain from Planet Arous (1957)
An evil alien brain, bent on world domination, takes over the body of an atomic scientist, while a "good" alien brain inhabits the body of the scientist's dog and waits for an opportunity to defeat the evil brain.
An evil alien brain, bent on world domination, takes over the body of an atomic scientist, while a "good" alien brain inhabits the body of the scientist's dog and waits for an opportunity to defeat the evil brain.