Haunted by a life of abuse, Casey (Taylor-Joy) is kidnapped with two classmates (Richardson and Sula) and held hostage by a clearly insane man who calls himself Dennis (McAvoy). Except that he's actually Kevin, who has 23 distinct personalities and is in treatment with Dr Fletcher (Buckley), a pioneer in the field. While Dennis has plans for these girls, supported by fellow personality Patricia, his 9-year-old alter-ego Hedwig thinks this is all a game. And all of Kevin's personalities are playing with something dangerous here, in fear of a shadowy identity they call the Beast.

Shyamalan gleefully drops hints and innuendo into each scene, using cleverly disorienting photography and sound while withholding information from the audience. Details emerge through flashbacks of Casey on a hunting trip with her dad and uncle (Arcelus and Henke), plus scenes in which Fletcher interacts with Kevin's various personae. She may be an expert in reading his face, but she of course has no idea what he's up to.

McAvoy throws himself into the performance, creating six or seven distinct characters who are lively, funny, menacing and/or charming. They're all rather camp, lending adding a darkly humorous edge. And most are eerily likeable even as they're impossible to trust. It isn't until the final scenes that the character tips over into cartoonish ghoul. Meanwhile, Taylor-Joy is a terrific heroine. Even if some of her plot points are undercooked, she plays the role in a way that pulls the audience in.

The result is a movie that's relentlessly creepy, packed with nervous interaction in very grim settings. But it drags through a few too many turns of the plot and a reluctance to cut loose with edgy mayhem when histrionics will do. The chief joy here is watching McAvoy cycle through his colourful range of characters, even if the connection with identity disorders is lost along the way. And while Shyamalan can't resist adding a witty sting in the tale, he really should have known better than to exaggerate a real mental condition for cheap thrills.

themes, violence, language

10.Jan.17