Synopsis

In a refined establishment of traditional Japanese cuisine, Kogoro, Ran, and Conan observed a peculiar service: dishes arrived via a small, computer-guided boat navigating a stream that flowed beneath the restaurant. The tranquility was shattered when a murder took place. Conan, observing the scene, deduced that the perpetrator must have operated in complete isolation, utilizing the stream as a clandestine pathway to reach the room.