It's one of those mystery films which leave you wondering even after you've finished watching the film. This is the essence of the true mystery that it can't be known totally. There are people who think that the doctor was guilty and there are people who think that the climax was open ended for the interpretation.
Roman Polanski is master of tension and mystery. He does that in classical Chinatown and in The Tenant. This film is very tense right from the first few scenes because of the central character--a woman who is psychotic because of the past trauma. Much of the intrigue of the film is because of her---a role well played by Sigourney Weaver. You wonder that such a great mystery film can be made with just three characters---all of them confined to a close space and unable to think clearly. This masterpiece reminded me of Twelve Angry Men, because these films accomplish much without having a great space or range of characters, just by virtue of its script. I think this is how mysteries should be. I feel that this film is underrated. I feel that this film is flawless and I would rate it 10 out of 10.
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