After spending a decade in prison, a hitman learns that he has a daughter and just wants a chance at a normal life. But his former mob boss wants him back at any cost, sending merciless assassins after him.
When a devil-worshipping criminal network plunges Seoul into chaos, the police turn to Holy Night—a trio of supernatural demon hunters—to restore order and defeat the rising evil.
'Monster Cop' Ma Seok-do investigates an illegal online gambling business led by a former STS Baek and an IT genius CEO Chang. Ma proposes an unexpected alliance to Jang and begins hunting down the criminals.
Detective Ma Seok-do changes his affiliation from the Geumcheon Police Station to the Metropolitan Investigation Team, in order to eradicate Japanese gangsters who enter Korea to commit heinous crimes.
