The story of "Blood of Lone Wolf" is set in Hiroshima before the implementation of the "Anti-Yakuza Law" in 1988. Hideichi Hioka, who was assigned to the local police station, was responsible for investigating the disappearance of financial company employees together with detective Shogo Ohgami, who was rumored to be in collusion with the mafia. Hioka was confused by Ohgami's unusual investigation methods. At the same time, starting with the disappearance case, the struggle between the opposing mafia groups intensified, and at this time Ohgami came up with a bold plan... The original author of "Blood of Lone Wolf", Yuzuki Yuko, won the 69th Japan Mystery Writers Association Award, and this novel was evaluated by the industry as "Police novel x 'Unrighteous War'". The veteran actor Koji Yakusho and the popular young actor Tori Matsuzaka played Ohgami and Hioka respectively in the film. The combination of an old and a young detective is quite interesting, and the supporting cast also includes big names such as Yosuke Eguchi and Yoko Maki.