While this movie does take some very creative liberties when it comes to talking about multiple personality disorder (nowadays called dissociative identity disorder), it does make it clear as to how it works in-universe. James McAvoy plays a man with twenty-three different personalities, and while a few of them are more dominant than the other, many seem to worship this yet-to-be-seen twenty-fourth one known as The Beast. It’s a great thriller, and many regard it as a return to form for the director, M. Night Shyamalan. I certainly did, at least.
Part of what makes me uncomfortable is McAvoy’s performance, and I don’t say this as a bad thing. As an example, I like to reference Imelda Staunton’s performance as Professor Umbridge in the Harry Potter movies. She acts the role so well that she makes it easy to hate everything about her character; similarly, McAvoy manages to fit the roles of the many personalities in such a way that I find it quite believeable. Aside from just wearing different clothes when the other personalities manifest, his speech patterns, accent, posture, mannerisms – everything about him changes. There’s even a scene where he’s speaking with his therapist and he changes from one to another. He doesn’t get up from the chair at all, but instead the camera just stays focused on him for a full minute and you watch as the change happens. It’s creepy, but such a great execution.
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