Quite unique but suffers a bit due to lack of clear exposition. The acting overall is very good; many of the actors give memorable performances, unlike most horror films.
Some of the effects were are little unconvincing or a little off, which is highlighted by the more practical effects. The cinematography is great, allowing for tension to build throughout. The film has a large amount of gore, which is greatly unsettling. However, the ending could have been explained a lot better than it was. It was quite confusing and leaves you with a lot to consider.