- The dead body of Tanimoto Masahiro, a police officer who works at a police post in Akabane precinct, is found in playground equipment at some park. His temple had been shot with his own gun and there is high possibility that it is murder because that gun has gone missing. But Kuraishi resolutely declares, "It was a suicide." Godai Keiichi, the head of the Criminal Affairs Beureau, is worried about criticism from the public and checks with Kuraishi, but Juraishi persistently sticks to his suicide theory. However, there is one thing that bugs Kuraishi. Tanimoto's whistle cannot be found. Is it in the possession of the criminal who had taken the gun? Or was it dropped somewhere?