MOTHER

In a number of not insignificant respects, the experience a South Korean will have when viewing the new whodunit from writer-director Bong (“The Host”) Joon-ho will differ from that of an American watching the same movie. The story concerns a mentally disabled young man accused of murder and the widowed mother who pursues the real killer when police lock him up and close the case.

Few American moviegoers will appreciate, for example, the extreme makeover undergone by former teen idol Won Bin in his preparation for the role of twentysomething local joke Do-joon. The character’s a marvelously intricate creation carried off brilliantly. Just as few-and this is truly a shame-are likely to find themselves in on the filmmaker’s little joke in casting 68 year old Korean television legend Kim Hye-ja as the title character. The actress has spent much of the past thirty years playing traditional maternal parts. Her role here will have shock value audiences in the west won’t begin to imagine. Conversely, how many South Korean viewers will describe the picture as Hitchcockian?

More important, of course, is what viewers everywhere will share: a cinematic experience that takes us into rarely explored psychological terrain, almost never proceeds as we predict and craftily subverts the genre.

Hye-ja’s unnamed character is an herbalist and acupuncturist with a tiny shop in a nondescript village. Her real job though is keeping her son out of trouble. Do-joon would be at the mercy of a thousand forces even if his best friend, Jin-tae (Jin Gu), weren’t a local hustler and thug.

When he asks Do-joon whether he’s ever slept with a woman, the young man answers “my mother.” We realize this isn’t the simple bit of comic dialogue it seems at first when Do-joon crawls into bed with her later that very night, resting a hand on one of her breasts and in response hearing only “It’s so late.”

The plot hinges on what happened only moments before. Do-joon drinks too much while waiting for Jin-tae at a bar and is asked to leave by the owner after trying to pick up her daughter. On the way home he crosses the path of a fetching school girl named Ah-jung whom he follows until she disappears down a dark alley. In the morning her body is found neatly folded over a hilltop balcony overlooking the town.

What initially appears a twisty riff on uncritical devotion slowly but surely reveals itself to be something infinitely more twisted. Joon-ho is a master at lacing pulse pounding suspense with off beat humor but here adds a new darkness to the mix. It’s easy to understand, for example, why a parent would try to protect her cognitively challenged child. But what are we to make of the fact that, when he was five, she tried to end his life?

This is a constantly surprising, subtly acted and masterfully directed mystery propelled by Lee Byeong-woo’s score which echoes Bernard Herrmann’s soundtrack for “The Wrong Man” one minute and Stanley Myers’ tender guitar theme from “The Deer Hunter” the next. The movie opens, in fact, with a sequence in which we watch Hye-ja alone in a swaying field dancing gently to this music.

The instinct of the viewer, I think-whether Korean or American-will be to interpret this as a gesture of victory and contentment. The next two hours flash back through the days leading up to that dance in the field and astound us as to the measure of our miscalculation. With a final act likely to leave M. Night Shyamalan’s jaw on the theater floor, Joon-ho’s latest features the mother of all surprise twists.