The scene is Tokyo, a city full of decadently grotesque desires and malice. It is late at night and Ishigami, a salesman for a pharmaceutical company, unexpectedly has a gun in his hand. Ishigami, weary of everyday life, only feels fulfilled when he holds the gun. A sense of justice against a distorted society awakens in Ishigami and, while pretending to be a detective, he starts to carry the pistol around looking for bad guys. Before long Ishigami is chasing after a murder case, crawling deeper into the city until he is swallowed by the massive, crooked darkness. The entire movie is covered by the gloom of night, like film noir overflowing with a psychotic mood.