I really enjoyed the atmosphere and visuals of this movie. The dream scene's designs are so cool, I would watch them all in a row, really dark art there.
This is the strongest aspect of the movie.
The sound is really good too, adds up a lot to the atmosphere, creating a creepy, mysterious vibe.
Good performances throughout, most of the characters are quite solid in their parts.
Story wise, there's a good tension and mystery feeling through the first two acts, but the third one feels stretched and even a bit incoherent by times. This is fixed my the very ending's twist, but I'm not too sure I liked the it. It's a valid one, but it might feel cheap or overdone for some people. I don't think it's a brilliant ending, but it serves well to a decent movie.
As I say on the title, there's a massive spoiler on the images of this movie on IMDB, so don't look at them if you haven't watch the movie yet.
I recommend this movie to visual lovers and if you're in the mood of a very slow paced movie.