. While the original is a brutal "cat-and-mouse" game between a secret agent and a psychopath, its themes of love and vengeful obsession were adapted into a more commercial, musical format for Hindi audiences. The Story: A Descent Into Darkness
At its core, the story is deceptively simple. Kim Soo-hyun (played by Lee Byung-hun), a secret service agent, sees his life shattered when his fiancée is brutally murdered by a serial killer, Kyung-chul (Choi Min-sik). Instead of a straightforward revenge story where the hero kills the villain, the film takes a twisted turn. Soo-hyun decides that death is too easy a punishment. He captures Kyung-chul, beats him to the brink of death, and then lets him go—turning the pursuit into a terrifying game of catch-and-release.
"Oldboy" (2003), "The Merciless" (2017), and "Memories of Murder" (2003) are some similar movies that explore themes of revenge, violence, and darkness.