A movie about a priest who's transformed into a vampire might inspire some deep noodling about Catholic liturgy, no doubt. And that could be what Park Chan-wook, the waywardly brilliant South Korean director (and onetime philosophy student), had in mind in making his latest film, "Thirst." But just when we've set our brains on ponder, the picture muddies all hope of contemplation with flashes of the fearlessly eccentric imagery for which Park has become famous, and some of the slurpiest sex scenes to be found in any recent R-rated movie.

Park's narratives are ... challenging, you might say. Here, the virtuous priest, Sang-hyun (played by frequent Park associate Song Kang-ho), after volunteering to be a test subject in the search for a cure for a mysterious disease, finds himself developing a taste for blood. At first, being a gentle soul, or possibly just lazy, he siphons it out of comatose patients at the hospital where he ministers. Then he becomes involved with Tae-ju (irresistibly ornery Kim Ok-vin), the unhappy wife of his childhood friend Kang-woo (Shin Ha-kyun, another Park vet). Tae-ju eventually learns the priest's secret and is intrigued ("Vampires are cuter than I thought"). Soon he puts the bite on her — but quickly regrets it. Tae-ju has none of Sang-hyun's spiritual conflicts about bloodsuckery (she's not Catholic!), and before long she's mocking his nonviolent approach to slaking the ancient thirst. ("You easy-blood-drinking coward!") An instinctive traditionalist, she eagerly embarks on a round of throat-ripping depredations among the local populace, resulting in the sort of problems that a hundred years of vampire movies might lead you to expect.

The movie is rather long, given its deliberate pace (it meanders for well over two hours), and there are the usual Park confusions. Tae-ju's tiresome husband appears to keep dying and then reappearing, repeatedly. (I quickly gave up trying to figure out what his deal was.) The point of the priest giving the girl his big battered shoes to wear was likewise lost on me. And there are more mah-jongg games going on than an uncultivated Westerner might think strictly necessary.

But working once again with cinematographer Chung Chung-hoon and lighting director Park Hyun-won, the director has created another series of swooningly strange scenes and images. The lubricious sex interludes, slathered in blood and heightened with over-amped heavy breathing, are strikingly original. The picture may not be as spellbindingly gorgeous as some of Park's previous films — "Sympathy for Lady Vengeance," say — but the long concluding shot of the star-crossed couple on a cliff high above the sea is a stunner. All of this, plus lines like "We can put the blood in Tupperware and keep it in the fridge" — who can resist? Once, anyway.

Don't miss Kurt Loder's reviews of "Funny People," "Not Quite Hollywood" and "The Collector," also new in theaters this week.

Check out everything we've got on "Thirst."

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