This is a psychological thriller or mystery containing many aspects of a ghost story. The viewer has to decide whether some kind of ghost of demonic force is involved in the events. The main character could be suffering from a dissassociative identity disorder; perhaps he is haunted by the spirit of a murderer; perchance both. I think the team really pulled it off. The bloodiness is fairly tame by today's standards. There was one brief sex scene - which coincidentally triggered the main character's decent into darkness or madness - again fairly tame. I loved how the background sound became percussive at certain points although I don't know if others would notice this. I felt drawn into the movie by the dark, dimly lit scenes, the viscerally evocative motifs - for instance, a big mysterious hole at the back of the house.