The Mole Song: Undercover Agent Reiji

Reiji Kikukawa (Toma Ikuta) is officially fired from active police duty for gross misconduct, but his strong sense of morality leads him to be recruited as an undercover agent by Special Agent Kazumi Akagiri. He infiltrates the Sukiya-kai, a ruthless yakuza gang, and becomes friends with Masaya Hiura (Shinichi Tsutsumi), who is impressed by Reiji's humor and brings him into the clan. As Reiji gains the trust of the Sukiya-kai, he must navigate the complexities of organized crime and his own moral code, all while keeping his true identity as an undercover cop hidden.