M. Night Shyamalan's name has become a bit of a punchline in the last decade. His promising career derailed by relying too much on gotcha twists that overcame the narration (The Happening, Lady in the Water) and an unfortunate flirtation with mainstream blockbusters (The Last Airbender, After Earth), it became custom to omit his name from trailers and marketing materials to avoid scaring away potential audiences who had been burned one time too many. But to Shyamalan's credit, he keeps working undeterred by his string of disappointments and failures, and that determination paid off in 2015 with The Visit, a modest hit in the found footage horror genre that was an imperfect but welcome return to his suspense roots. Now he's back behind the camera again with Split, promising another taut thriller akin to the movies that made his name. Could this be an antidote to the horror movie shovelware that has come to define January and February?

The force behind Split is Kevin (James McAvoy), a man who breaking into a car containing three girls, Casey (Anya Taylor-Joy), Claire (Haley Lu Richardson) and Marcia (Jessica Sula), taking them captive and holding them in a dingy basement with no exit in sight. But Kevin isn't actually Kevin (or isn't just Kevin, rather), and it becomes evident quickly that he is a man living with dissociative identity disorder that has fractured his psyche into 23 distinct personalities. He has been keeping them somewhat in check with the help of Dr. Fletcher (Betty Buckley), but some of the more sinister personalities have managed to take hold. They believe in an all powerful ur-personality, The Beast, with enhanced physiology and supernatural abilities, and have kidnapped the girls as sacrificial tribute. Casey sees this as an opportunity to use the weaker personalities against each other in order to find a means for escape.

It's plain to see why an actor the likes of McAvoy would be drawn to a project like this; it's quite the actor's showcase for him as he jumps from identity to identity. One scene he's an officious and domineering man with obsessive compulsive disorder who needs glasses, the next a refined, polite British woman followed by a nine year old with a speech impediment. And McAvoy is fully committed to the bit, giving each of his characters their own tics and physical characteristics and keeping that consistent throughout. It's demanding work, especially when the personalities begin to cross over into their own interpretations of each other. McAvoy is consistently compelling, pitiable and sinister in equal parts, a sort of treatment of mental illness not as weakness or stigma, but a king of strength, an unlocking of the potential of the brain and by extension the body. This can be problematic at times, but McAvoy sells it well, and the narrative manages to support itself by the end. The power dynamics at play within his head are surprisingly well-drawn, and Shyamalan does a good job drawing out the exposition through psychotherapy sessions that are still founded on character, and rarely feels forced or overwrought.

As for the girls in peril, both Anya Taylor-Joy (The Witch) and Haley Lu Richardson (The Edge of Seventeen) seem to have taken advantage of the momentum they created in their breakout roles from 2016 (though both remain arguably criminally underseen). Taylor-Joy is the most central of the trio, a loner who seems to be a bit too familiar with trauma and abuse than someone her age probably should be. She's a worthy foil for Kevin and his legion of personalities, resourceful and sly and guarded despite fearing for her life. Her arc does point to the film's greatest weakness, though, as the third act makes it clear Shyamalan is far more interested in Kevin and his plight than Casey, the presumptive protagonist of the movie. Split seeds in a backstory for Casey throughout via a series of flashbacks, and while it does feature into the story, it does so in a perfunctory and unsatisfying deus ex machina that threatens to have the film go out with a whimper. It's a good thing, then, that the patented M. Night Shyamalan Twist Ending is quite elegant and satisfying, a textbook case of recontextualizing the story instead of redefining or reinventing it. It papers over the cracks that form in the final third, managing to let the story breathe instead of collapsing on itself.

Regardless of its shortcomings and misgivings, Split feels the most like classic Shyamalan since Signs and The Village. The performances of McAvoy and Taylor-Joy are uniformly excellent, and It Follows cinematographer Mike Gioulakis proves he's no flash in the pan with another helping of taut, suspenseful camera work. As a sort of intersection of Identity and 10 Cloverfield Lane, it doesn't always break new ground, but it works quite well as a piece of genre execution, something all too rare in most new January releases (like, say, The Bye Bye Man). Split doesn't have the confidence of The Sixth Sense or Unbreakable, which remain the cream of the Shyamalan crop, but it isn't far off, and provides more building blocks for him to get back to the sort of filmmaking and storytelling that made him a name in the industry. It won't be an easy road to travel, but his comeback is showing promise.