FAQ

Upon his death, French magistrate Simon Cordier (Vincent Price) leaves a diary to be read by his survivors. In it, he tells how an invisible entity called the 'Horla' insidiously took over his body, his mind, his will, made him commit murder, and drove him mad.

Diary of a Madman is based on a short story, "The Horla" by French writer Guy de Maupassant [1850-1893]. The story was adapted for the movie by American film-maker Robert Kent, who also co-produced the movie.

Simon contracted the Horla when he accidentally killed condemned prisoner Louis Girot (Harvey Stephens), who insisted that he had been taken over by a spirit that forced him to commit his crimes. Where the Horla came from before that is not addressed in the movie. The Horla tells Simon that he actually lives, solid but unseen, alongside humans and is attracted by evil. Wherever there is evil, the Horla can get in.

The story takes place in 19th century France, specifically 1886.

Yes. It's called "A Woman" and was written by German writer Heinrich Heine [1797-1856]. The poem is in the public domain and can be read on numerous websites including here and here.

Yes. "The Horla" is in the public domain and may be read and downloaded for free on numerous websites such as the Gutenberg Press.

Simon resists the urge to kill Jeanne D'Arville (Elaine Devry) when he notices the reflection of a crucifix on the blade of his knife. He asks Father Raymonde (Lewis Martin) for sanctuary in the church but, when they begin to cross the street, the Horla causes a carriage driver to lose control of his horses, barely missing Simon and the priest. Aware that the Horla now intends to kill him, Simon asks Father Raymonde to catch up with Jeanne and tell her to come to his house. Simon then goes home to wait. When Jeanne shows up, he gives her a chest with the diary inside and tells her to quickly leave. He then locks himself in his study. When the Horla enters through the French doors, Simon tosses an oil lamp at the doors, setting the curtains on fire. With no means of escaping the room, the Horla begins to frantically search for an exit. The fire continues to spread until the Horla is engulfed in flames. Simon tries to get out of the room but drops the key into the flames and cannot retrieve it before a burning beam falls on him. In the final scene Jeanne, her father, Father Raymonde, Simon's servants, and the police captain sit around the table after reading Simon's diary. Jeanne asks the captain whether he now believes in Paul's innocence, and he agrees. They then discuss whether the Horla was real or just something from Simon's imagination, and Father Raymonde reminds them of Simon's warning that, wherever evil exists in the hearts of men, the Horla can get in.