This routine continues for 15 years. He is never told who has imprisoned him, or why. He watches TV until it becomes his world. He fills one journal after another with his writings. He pounds the wall until his fists grow bloody, and then hardened. He screams. He learns from TV that his blood and fingerprints were found at the scene of his wife's murder. That their daughter has been adopted in Sweden. That if he were to escape, he would be a wanted man.

"Oldboy," by the Korean director Park Chanwook, watches him objectively, asking no sympathy, standing outside his plight. When, later, he does talk with the man who has imprisoned him, the man says: "I'm sort of a scholar, and what I study is you."

In its sexuality and violence, this is the kind of movie that can no longer easily be made in the United States; the standards of a puritanical minority, imposed on broadcasting and threatened even for cable, make studios unwilling to produce films that might face uncertain distribution. But content does not make a movie good or bad -- it is merely what it is about. "Oldboy" is a powerful film not because of what it depicts, but because of the depths of the human heart which it strips bare.

The man, named Oh Dae-su (Choi Min-Sik), is a wretch when we first meet him, a drunk who has missed his little daughter's birthday and now sits forlornly in the police station, ridiculously wearing the angel's wings he bought her as a present. He is not a bad man, but alcohol has rendered him useless.

When he suddenly finds himself freed from his bizarre captivity 15 years later, he is a different person, focused on revenge, ridiculously responsive to kindness. Wandering into a restaurant, he meets a young woman who, he knows from the TV, is Korea's "Chef of the Year." This is Mido (Gang Hye-Jung). Sensing that he has suffered, feeling an instinctive sympathy, she takes him home with her, hears his story, cares for him, comes to love him. Meanwhile, he sets out on a methodical search to find the secret of his captivity. He was fed pot stickers, day after day, until their taste is burned into his memory, and he travels the city's restaurants until he finds the one that supplied his meals. That is the key to tracking down his captors.