Ouroboros(2015)

Ouroboros is a Japanese series based on a popular manga about two men bound by childhood trauma and a promise of revenge. Ikuo and Tatsuya grew up together in an orphanage and witnessed their beloved teacher murdered by a corrupt policeman. Twenty years later, their paths diverge: Ikuo becomes a detective at Shinjuku's second police station, working alongside elite investigator Mizuki, while Tatsuya rises through the ranks of organized crime. When their investigation into a series of cases intersects with the criminal underworld, the two are forced to confront the conspiracy that destroyed their past and the moral cost of their diverging quests for justice. The series explores loyalty, corruption, and whether redemption is possible when vengeance and duty collide.