After a drunken night on the town, an ordinary Seoul businessman, OH Dae-su, wakes up in the morning to discover he has been locked up without explanation in a mysterious prison. After fifteen years, Dae-su suddenly and inexplicably finds himself freed. A voice on a cellphone taunts him into discovering who kept him imprisoned. Dae-su plunges into a world of competing vengeance, his own drive for revenge matched by the equally implacable and Byzantine...

A second-tiered member vying aggressively for the position of godfather is restrained by the current mob boss, who isn't officially eligible for reelection, which leads to a bloody and cutthroat battle of wills between the two men.