Case Closed (1996)

Season 10

Episode 27: The Small Eye-Witnesses

The 3 Detective Boys are playing 'make-believe detectives' when they encounter a real case. A man is killed right in front of them, wrapped up in a sheet and thrown into a truck. The Detective Boys hide in the back of the truck with the body and the killer drives to a forest and buries the body. The next day the Detective Boys tell Conan and Mouri about the murder, and Conan is able to tell where the body was buried from the descriptions of what the truck drove past and the culprit is caught.