Directed by Lucio Fulci who is apparently a respected name amongst gore film fans. I watched this film with increasing confusion as it made less and less sense. There are moments of extreme gore, so if you like skin tearing and blood spurting then you'll like this film. The gore that you see is quite excessive but also obviously fake, so it never feels unwatchable. The dubbing from Italian to English is quite laughable, I assume it is dubbing just because the voice acting is so stilted and wooden. It's not a film worth watching for the plot because the story is really terrible. I don't know if this film is a standalone or part of a genuine story trilogy, if it is it might explain some of the back story I just wasn't getting.
This film seems to suffer terrible translation difficulties. There are lots of funny looks and close-up eyes-only shots. They might have meant something but to me they were laughable. There is a creepy librarian character who is just plain weird but, apart from being weird, seems to play no part in the story. I don't know if this version is a version that has been cut or not, it was a film that originally suffered heavy cutting by the BBFC. It may explain some of the incoherence.
I can't really recommend this to anyone apart from fans of gore films.