I'll make this very generalised as to avoid spoilers.
Pros: Creepy atmosphere, sets up well for jump scares, kind of creepy for the first 20 minutes but then becomes repetitive.
Cons: Loses it's shine very quickly, becomes very very obvious and boring, producer relied too much on jump scares, a lot is left unexplained....
All in all, 1/5 for me. It had potential, it had a good setup, but it was delivered poorly and it missed the mark.