I need to identify a Horror movie probably made in the 60's, maybe late 50's, where a man, who lives with his elderly mother, kills enemies by passing the victim a piece of paper (unknown to the victim) which causes a demon-like creature to pursue and kill the victim at a certain time of night. The victim often hears a melody (in his mind). There is a séance scene. Also, there a scene where a man in a mental institution explains passing the paper note to another in order to save his own life. He then goes mad and jumps out a window to his death. The hero has been passed the paper note and most of the story follows him trying to understand the meaning of it and his fate. I cannot remember the names of any of the actors.

Curse of the Demon

Yes, that's the film. Thanks so much Quinn F. This is not the first time you have helped me. You're the best Quinn F.

Glad to help :)