2020 film directed by Emerald Fennell

Kyung-chul is a dangerous psychopath who kills for pleasure. Soo-hyeon, a top-secret agent, decides to track down the murderer himself. He promises himself that he will do everything in his power to take vengeance against the killer, even if it means that he must become a monster himself.

William Munny is a retired, once-ruthless killer turned gentle widower and hog farmer. To help support his two motherless children, he accepts one last bounty-hunter mission to find the men who brutalized a prostitute. Joined by his former partner and a cocky greenhorn, he takes on a corrupt sheriff.

2005 South Korean film directed by Park Chan-wook

A deaf man and his girlfriend resort to desperate measures in order to fund a kidney transplant for his sister. Things go horribly wrong, and the situation spirals rapidly into a cycle of violence and revenge.