When loner teenager Casey (Taylor-Joy) makes her way home from a party with popular girls Claire (Haley Lu Richardson) and Marcia (Jessica Sula), the violent Dennis (McAvoy) gasses them and takes them to his prepared underground bunker. But neat-freak Dennis isn't just Dennis – he's also Patricia, a well-spoken English lady, designer Barry, and Hedwig, a hip-hop loving nine-year-old; just four of the twenty-three identities of Kevin, a patient in the care of Dr. Fletcher (Buckley), who believes Dissociate Identity Disorder may be the next step of evolution and suspects there's a twenty-fourth personality. Dennis and the rest warn the captive girls they are to be 'sacred food' for the imminent Beast…
By far and away M. Night Shyamalan's strongest film since his best, 2000's Unbreakable, Split doesn't behave like a Shyamalan movie. The sombre atmosphere is gone, replaced by an air of dread, with the opening abduction sequence particularly unsettling. The framing is strange too with Taylor-Joy's extreme close ups jarring with McAvoy's wide shots, while sitting characters would suddenly stand with Shyamalan letting the scene play out with their top halves cut off. Okay, so there's the expected twist but again this one is different and it's one that will divide audiences, being incredibly silly and unnecessary but also potentially fun.
Shaven headed, McAvoy doesn't need a change of costume to morph into the different personalities – his voice changes and there's something in his eyes that darken or widen or flicker. His Patricia doesn't quite convince but his happy-go-lucky Barry is fun, the intense Dennis terrifying and the naïve Hedwig a dote. When all these personalities battle for 'the light' (that time when one persona momentarily dominates) at the same time, McAvoy has the unenviable job of running through all the identities at once like a rolodex of performances. It was an impossible task to pull off and Shyamalan deserves a rap on the knuckles for thinking anyone could do it and not diminish the performance and what is a very important scene.
But as all eyes will be on McAvoy, Betty Buckley and The Witch's Anya Taylor-Joy quietly doing what they can to steal the film away from him. Buckley's kind, understanding doctor is the calm amidst the chaos around her and whenever she's on screen she elevates the scene. Taylor-Joy's Casey feels like a character not suited to this kind of story: She's not like Marcia and Claire, who understandably are stupefied by their monstrous abductor, but Casey is always just oddly quiet. The reasons behind her ability to keep it together slowly revealed in flashbacks when as a child she went on a hunting trip with her father and uncle.