There's a twist to M. Night Shyamalan's Split that caught me flat-footed: It's actually a good movie, something his past decade made as hard to predict as Bruce Willis being dead in The Sixth Sense.
Split is a tidy example of lurid understatement, its themes ripe for nastier treatment than Shyamalan offers, grindhouse stuff served with vegan restraint. There's no need for explicitness with two dozen deranged weirdos prowling around and one actor playing them all to the hilt.
James McAvoy is a pleasure to observe taking everything seriously. He is giddily invested in each psychotic shard of his role's demented nature, chiefly Dennis the clean freak who kidnapped three teenage girls, Hedwig the lisping 9-year-old boy with a crush, and matronly Patricia, mid length skirt and all but a wig. Those kidnapping victims never know who's coming through the dungeon door.
Nor do those girls take their predicament laying down, especially Casey (Anya Taylor-Joy), an outcast pressed on classmates just before their abduction. "Why do you act like you're not one of us?" grills Claire (Haley Lu Richardson) when Casey isn't immediately down with an escape plan. Why doesn't anyone wishing to survive movie psychos, like virgins at summer death camps? Cryptic flashbacks to Casey's deer hunting trips with her father and uncle will explain and unsettle satisfactorily.
Taylor-Joy modernizes her breakout radiance in The Witch, not a scream queen but fearfully composed in the face of supernatural events. Casey is resourceful and shrewd, at one point attempting to turn her captors against each other, a classic hostage strategy. With the captors all in one person, Shyamalan has a nifty hook on which to hang McAvoy's revolving door performance.
Meanwhile, a psychologist (Betty Buckley) has been treating whomever McAvoy's playing, chiefly an aspiring fashion designer named Barry. The shrink has an ulterior motive for keeping Barry and his pals on the street. That allows Buckley to unspool Shyamalan's plumpest exposition, of watershed trauma, ambitious theories and why some of her patient's personalities are "banned from the light."
In return, whoever's on the couch at the moment promises "the Beast" is coming. "For the eating of the impure young?" the psychologist asks. That's the guy.
From that point Split accelerates from slow-burn thriller to one of the more deranged, don't-dare-spoil third acts in memory and a coda cameo that lifted me from my seat. Shyamalan hasn't goosed a crowd this successfully since Signs. As someone who'd written him off, it's fun to have been wrong.
Contact Steve Persall at firstname.lastname@example.org or (727) 893-8365. Follow @StevePersall.