Kaoru Utsumi, a detective from the Investigation Division 1 of the Metropolitan Police Department, came to consult with a physicist, Manabu Yukawa, who returned to the United States. A popular daughter in the town who suddenly disappeared was found dead a few years later, and the suspect was acquitted in the murder of a girl who was once in charge of Utsumi's senior detective Shumpei Kusanagi during the same period as Yukawa and college. It was a man who became. However, he is released again due to insufficient evidence. The man returns to the town where his daughter lived, appears openly in front of the bereaved families, and provokes them, covering the entire town with an air of hatred. And on the day of the autumn festival parade, the man died. Everyone who has the motive to kill a man has an alibi, and the cause of death is unknown. Yukawa, Utsumi, and Kusanagi challenge this super-difficult problem.