Old Boy is a 2003 South Korean film directed by Park Chan-wook. Oldboy is the second installment of The Vengeance Trilogy, preceded by Sympathy for Mr. Vengeance and followed by Sympathy for Lady Vengeance.

The movie follows the story of Dae-Su who is locked in a hotel room for 15 years without knowing his captor's motives. When he is finally released, Dae Su finds himself still trapped in a web of conspiracy and strangeness. His own quest for vengeance becomes tied in with romance when he falls for an attractive sushi chef.

The film won the Grand Prix at the 2004 Cannes Film Festival and high praise from the President of the Jury Film critic Roger Ebert has claimed Oldboy to be a "...powerful film not because of what it depicts, but because of the depths of the human heart which it strips bare