It would be easy to dismiss or to disgrace Split as taking advantage of mental illness for the sake of a genre effort, but writer/director M. Night Shyamalan's newest psychological thriller - the best in more than a decade, by this critic's estimation, from a filmmaker once hailed as the next Steven Spielberg - is trickier and smarter than that. It features two characters with some form of mental illness. The first is something of the antagonist of the piece, a man seemingly cursed with 23 personalities as symptoms of his Dissociative Identity Disorder (or DID, formerly known as Multiple Personality Disorder). The medical science here is iffy but believable within the constraints of Shyamalan's fantastical vision: There can be personalities within DID that showcase abnormal abilities, such as the ability to lift far more weight than another identity could or an immunity within one identity to allergies from which another might suffer.
The identity of the other character suffering from some form of mental dysfunction should not be revealed here, but Shyamalan's use of flashback is exceptional in the way each piece builds enormous tension within the story being woven into the present and provides crucial insight that will likely require multiple viewings to parse out. As is his custom within the thriller genre, Shyamalan twists this concept into one that borders on the fantastical for so long that a third-act shift toward genuine fantasy is surprisingly subtle. I'm getting ahead of myself, of course. It's important to provide context. The man with almost two dozen personalities may or may not be named Kevin, although he might also be Dennis or perhaps Barry. The complexity of this character is such that it isn't quite clear which identity birthed which. By the end, it's still not quite clear, for the record.
The uncertainty also lies in James McAvoy's performance as all of the identities we see (Still others are named in one shot, although there are only a handful onscreen). Dennis is obsessive-compulsive in his tendencies toward cleanliness. Barry is a slightly effeminate lover of fashion who can design clothing. Hedwig is a nine-year-old boy. Patricia is a woman with an English accent. Orwell has encyclopedic knowledge of history. McAvoy is utterly convincing when asked to shift between these various identities, and his scenes with Dr. Karen Fletcher (Betty Buckley, warm and inviting in a terrific performance), whose beliefs regarding DID drive the narrative toward its ultimate destination and inform a series of climactic revelations, are some of the film's best.
The plot regards Dennis' criminal activities with a trio of girls - loner Casey (Anya Taylor-Joy in a tricky performance that must juggle the weight of the past with a fight in the future) and popular girls Claire (Haley Lu Richardson, who is mightily impressive in a role that should provide her with others in the future) and Marcia (Jessica Sula) - whom he has kidnapped and on whom he performs a series of social experiments. Is Dennis running things, though? Is Patricia? What gives with Hedwig's curious warnings about a "beast" that is currently on its way to get them? The film shifts between Fletcher's exploration of her various hypotheses while in sessions with Kevin/Dennis/Barry/everyone else and the girls' attempts to escape. The former is given a thoughtful edge that toes but never quite crosses the line of exploiting this illness.
The point, elucidated by Fletcher in the opening act, is that perhaps dissociative identities are the closest human intellect has gotten to understanding the supernatural. Shyamalan's twist on this idea - perhaps the only "twist" here, unless one counts the director's distracting last-second attempt to connect the universe of this film to another one he made - is only made known by a climax that layers the past of one character onto the actions she must take in the present and builds upon itself in a way that is consistently surprising, involving, and ultimately tragic. It's troubling, too, distancing the film from a greatness that it could easily achieve with less blatant manipulation. But horror, especially of the psychological kind, is constructed to manipulate the audience. It's just a matter of the variation. Split is a striking example of the kind of manipulation that works because it doesn't cheat along the way.
James McAvoy (Dennis/Patricia/Hedwig/The Beast/Kevin Wendell Crumb/Barry/Orwell/Jade), Anya Taylor-Joy (Casey Cooke), Haley Lu Richardson (Claire Benoit), Jessica Sula (Marcia), Betty Buckley (Dr. Karen Fletcher), Brad William Henke (Uncle John), Sebastian Arcelus (Casey's Father), Izzie Leigh Coffey (Younger Casey).
Directed and written by M. Night Shyamalan.
Rated PG-13 (disturbing thematic content/behavior, violence, language).
Released on January 20, 2017.