In the year 203X, a security robot goes on a rampage in Shibuya. Nakamura Nao, a police detective with the public safety department, commissions detective Akechi Kogorou to solve the case... but Akechi, along with Inoue Ryou of the Boy Detectives Club, is already heading toward Hinomoto Heavy Industries, the robot's manufacturer. Meanwhile, Hanasaki Kensuke of the Boy Detectives club is pursuing a lost dog after receiving a report from the club's technical whiz, Noro Makoto. As Hanasaki corners the dog in an abandoned building, he finds himself face-to-face with a mysterious boy...