The Gangster, the Cop, the Devil is a 2019 South Korean action thriller film directed by Lee Won-tae. The film stars Ma Dong-seok, Kim Mu-yeol and Kim Sung-kyu. The narrative revolves around three characters: a serial killer, the gangster who was almost a victim of the killer and the cop who wants to arrest the killer. The cop and the gangster decide to join forces to catch the killer, but face challenges from their respective enemies at work.
The film was released theatrically in South Korea on 15 May 2019, and was also screened in the "Midnight Screenings" section at the 2019 Cannes Film Festival as well as at the 2019 Fantasia International Film Festival. The film received positive critical reviews.
(Summary from Wikipedia)