Oldboy is a South Korean film released in 2003. It was directed by Park Chan-wook and stars Choi Min-sik as the main character, Oh Dae-su. The film follows Oh Dae-su, who is imprisoned in a hotel room for 15 years without knowing his captor or the reason for his confinement. After he is released, he embarks on a quest to find out who imprisoned him and why, leading him to a shocking discovery.
Oldboy is known for its twisted plot, intense action scenes, and strong performances by its lead actors. It was highly praised upon its release and has since become a cult classic. If you're a fan of psychological thrillers and don't mind graphic violence, Oldboy is definitely worth a watch.