Takeshima Ryota is a new prison officer whose late father was also in the same profession. He sets foot in Kita Kanto Prison and sees corrupt prison officers quietly condone the bullying of prisoners and gamble inside. One day, Nakui Soichi from the Ministry of Justice becomes the new prison chief. Meanwhile, Ryota is given a rough welcome by Kamimiya Korekiyo, a prisoner with clout. A senior officer Akimura Shigeharu offers Ryota advice, but Akimura's baffling actions bewilder him. Then Nakui gives Ryota instructions in an attempt to cleanup the festering prison. On top of that, Kamimiya gets close to Ryota and hints that he knows something about his father's death. What is the justice and truth in the prison which is a closed world that no one knows...