Diary of a Madman

In this chilling 1963 horror film, Vincent Price stars as Simon Cordier, a French magistrate and amateur sculptor who unwittingly unleashes a malevolent entity known as the horla. The invisible yet corporeal being possesses a man it drives to murder and then turns its attention to Cordier, leading him down a path of madness and despair. As the horla's influence grows, Cordier's grip on reality falters, culminating in a tragic confrontation that ultimately destroys the entity - but at a terrible cost to the protagonist himself.