Drunken sad-sack Oh Dae-su (Choi Min-sik) wakes up one day in a seedy motel room from which he can't escape. Food is brought to him every day, but there is no window, only a television. Desperately, he begs to understand why he's there and for how long, but his jailers give no answers. Meanwhile, on the TV news, he sees that his wife has been murdered and he is the key suspect. Right when he's about to make some headway in escaping, he is released, waking up on the roof of the building. Fifteen years have passed. It really doesn't take long at all to find the culprit: a slick, spoiled-looking rich youth named Lee Woo-jin (Yoo Ji-tae). But there is a catch: If Dae-su kills him immediately, he'll never know the motive behind his imprisonment. So Dae-su goes on a quest for the truth, which is not one that he really wants to find. What follows is some truly messed-up stuff, but it's excellently presented.