Hunchback of the Morgue

Paul Naschy plays Gotho, a morgue hunchback in love with the one dying woman who was ever kind to him, who keeps her corpse and starts killing to protect it while a cellar-dwelling mad scientist puts his talents to worse use. It is the goriest thing Naschy ever fronted, wall to wall with acid-melted faces, a hacksaw and a slippery basement monster. It has also been dogged for fifty years by the rats in the crypt scene, which were real and did not survive the shoot.

Peak grim Naschy, and the one even his fans warn you about.