This is a wonderful mystery film. It's a film I would love to recommend to all Mystery buffs and if you're one please watch it without reading this or any other reviews further. This is one of those rare films which really shock you. When I recall such movies there are very few actually.
There are Mystery movies which are beyond comprehension. You might say that they're truly mysterious because their mystery can't be understood. David Lynch's masterpieces Inland Empire and The Lost Highway along with Roman Polanski's Chinatown are some great mysteries of this type. Then there are movies which need repeated viewings for a good understanding and still remain open for interpretation and discussion--that is, if you're wise enough you leave trying to interpret them after a while considering them a true piece of art. Christopher Nolan's Memento and Christopher Smith's Triangle are such films. I feel that most of the films with time-loop scenarios qualify for this category. Then, there's another category of Mystery films which resolve themselves with in their 90 or 120 minutes quota very well but still leave you awestruck because of strange twists which are quite unpredictable in nature. The Wicker Man(1973) is one such excellent Mystery movie.
Having seen some very ordinary Mystery flicks recently this movie took me in for a surprise. The Skeleton Key(2005) is another such flick. I would suggest you that you enjoy this film without great expectations--because being too tight on twist or expecting it all the time might ruin the passage for you. That's why I recommended you this film without reading this or any other reviews before watching this film. This is a very rare mystery thriller in my opinion and I highly recommend this to you. Thanks for reading!