Kim Hye-ja plays an obsessive mother in director Bong Joon-ho's new thriller, which focuses more on the odd relationship than the mystery. (Magnolia Pictures)
There's devotion and then there's something beyond devotion that resembles madness.
Director-writer Bong Joon-ho's masterful "Mother" examines (or questions) the difference between the two as a humble shopkeeper and mother (played with near-hysterical nuance by Kim Hye-ja) attempts to prove the innocence of her dim-witted son when he is accused of murdering a teen schoolgirl.
This is a mystery in the same way that David Lynch's "Twin Peaks" was a mystery, in other words, the mystery is secondary. As the story progresses in a small Korean town, it becomes more about the relationship between mother and son, about the odd characters involved and leaps of faith that end in broken legs.
It's obvious from the beginning that Mother is overly protective of her boy, Yoon Do-joon, and you quickly realize why -- Yoon is a complete dip. He hangs out with cool twenty-something minor thug Jin-tae (Ku Jin) but can't remember simple things, staggers his way through conversations, has no girlfriend (or prospects) and is a physical klutz.
All of which makes him an obvious suspect when a local girl is found dead. When the police pick him up for questioning, he can't put together a coherent sentence, much less an alibi.
Luckily, he's got Mother, who completely believes in his innocence. She coaches him in memory techniques while he's sitting in jail, then scrounges up the money for a lawyer, who eventually strikes a bargain to send Yoon to a mental hospital for four years instead of prison for 15 (murder apparently comes cheap in Korea).
But even that won't do for Mother: So she rejects the offer and begins investigating the murder herself, talking to the dead girl's friends and researching her background with the occasional help of Jin-tae.
The prospect of a middle-aged Mommy -- she and Yoon still sleep in the same bed -- hunting down a killer in the name of her own son's salvation sounds a bit like something that might come out of a Hollywood writer's factory (and indeed this film could be adapted, and ruined, quite easily by a major studio).
But director Bong -- who delivered the overrated cult hit "The Host" -- is working in an elaborately odd world in which cops are more incompetent than corrupt, hot leads run dead cold and Korean school kids act like mini-mobsters with hearts of ice.
The strongest and strangest relationship, though, is between mother and son. At first you figure Yoon is just a major loser. Then it seems Mother is a bit bananas herself. But eventually the tension between the two makes a mean sense and a black cloud drifts over all efforts.
Disturbing, enthralling and filled with interesting shots that reflect an artist's eye, "Mother" is a tale of dark deeds, botched moments and familial desperation that reveals itself slowly, with the tight pain of a needle being pushed too far into skin.