Mary is an unscary in-your-face horror that tries to be intelligent. It features the talent of Gary Oldman, and strong performances by Emily Mortimer, but even their dedication could not save this movie from sinking. There is a weak climax, and the lack of subtlety makes the story dull. It could have been more subtle by making it seem like one person is losing his or her mind, or focusing on how the characters descend to madness and culminate in a horrific climax. However, the story is weak and even the shots are done poorly. It fails to create claustrophobia or dread. The movie does deliver decent jump scares but its over reliance on this technique shows that it is not a scary story at all. If you are expecting a tense psychological horror on par with The Shallows, you will be sorely disappointed. If you are expecting a haunted house on water, it still fails. Don't waste time if you want to see it for itself. But if you want to see people screaming at the jump scares, you would probably enjoy it.