In a twist as sharp as the ending to each of his cinematic creations, M. Night Shyamalan (Signs, The Sixth Sense) returns to form with film that actually isn't terrible in Split.
On a dreary day in a dreary carpark, three teenage girls are kidnapped by a terse man in a buttoned-up shirt. Held captive in his underground bunker, it is revealed that this angry gentleman is just one of 23 personalities trapped within the body of a dissociative identity disorder sufferer named Kevin.
What do they want with the women? Who is "the beast"? Which person will we be meeting in five minutes? As is to be expected when you are dealing with the master of the spoiler, I can't answer those questions.
Playing the role of Kevin (and Barry and Hedwig and Patricia and many more) is the sensational James McAvoy (X-Men: First Class). Fleshing out at least nine characters - and providing snippets of many more - he is astoundingly malleable and effortlessly flits between a 9-year-old boy and a middle-aged woman.
Bringing some much-needed warmth and balance to the film is Betty Buckley as his psychiatrist, Dr Fletcher, endlessly caring and calm with all 23 of her patients. Kevin's captives, led by the enigmatic Casey (Anya Taylor-Joy) fill the role of shrieking teenage
victims sufficiently. They are forced to undress very early on in a way that feels too garish to be pointless, but fails to deliver on any trope flipping or sub version and mostly just feels weird and creepy.
That weird, misplaced tone extends to a lot of the film, which is frequently as fractured and erratic as the main character within.
Sometimes the tension coils extraordinarily tight and it feels like a hostage thriller, other times it becomes so quirky and offbeat it feels like a dark comedy where you aren't really allowed to laugh.
But there remains one indisputable fact: M. Night Shyamalan is still not messing about with his twist game, delivering a final scene that will leave those in the know reeling and those in the dark googling hastily.
Put it this way: if you thought the "I see dead people" reveal was the most powerful in his arsenal, you ain't seen nothing yet.
Opens Thursday, rated M