Pretty but Empty with a nothing ending. This is one good looking film, the sets, costumes and photography are outstanding, but the story builds, is mysterious, even a little confusing, then flops.
As you progress through it there are moments of 'get on with it' with catch up or ah ha moments, so you start to ask questions.
So does the main character and you join her in the quest for answers and an ending or exit. Here lies the problem, the movie finishes without giving those answers or exit, for you or the character, do people actually die, yes I think so, does she escape ? Not sure, do people return to normal life ? Not sure, and so on.
All that pretty filming is for nothing, it doesn't satisfy you, in fact you are a little annoyed, the shock value is taken away by 'oh no, that's not it, is it ?', the conclusion is a fail, leaving you...empty.