An elderly woman, Ume Matsumoto, complained to the First Investigation Department that her son Hirasaka, who runs a shoe store, had disappeared. The ominous foreboding of the First Investigation Department hit the mark, it turned out that the discovered unidentified body of the drowned man was Hirasaka. Moreover, the land in front of the station, owned by Hirasaka, was sold by someone. Suspecting that this is a planned murder, the Investigative Group, fearing the escape of the criminal, begins to act secretly, without creating an investigation headquarters.