Black Crow 0.

Prequel in the "Black Crow" series about an agency that resolves underworld troubles, set in Shinjuku's red-light Kabukicho district. The story focuses on the protagonist's hidden past. Rookie police officer Kanzaki gets posted to an area that has descended into anarchy. He gets a hand from fellow police officer Hyodo and they strive to do their jobs. Then, a criminal group's hideout gets burglarized and the incident escalates into murder.