Conan and the Detective Boys go to visit to Jun, one of their friend who is hospitalized. The boy wants to go to game room and asks his friends to help him sneak out. The children accept and Conan takes the place of Jun in the hospital. A man enters the room, however, believing that kidnaps Conan Jun and asks a ransom to the family. Once delivered the ransom, the police puts it in the van where he travels the kidnapper, but after being in a tunnel, it disappears into thin air as if it never was.