The body of Kou Fujisaki, who fell to her death, is discovered in front of an old building in West Shinjuku. Chief Sakamoto notifies Ushio, who arrives at the scene. Ushio thinks that this must be a murder, but according to Yamaji, who was at the scene before him, an eyewitness testified that Kou had jumped off the roof of the building, killing herself. Kou is someone who has lingered in Ushio's memory - as a suspect...