The Detective Boys head to a pound to witness animal control officers attempting to capture an alligator snapping turtle that is loose in the wild. A man named Jiro Nihonmatsu claims that it is his turtle; However, his story is inconsistent, as he claims he bought the turtles in Japan when they are only found in America. When an animal control officer finds two turtles, Nihonmatsu claims they are both his, causing Conan to become suspicious of him. After asking a vet to X-ray the turtles, they find a key to a storage locker where the money from a recent burglary is found. Conan reveals that after the burglary, Nihonmatsu hid the money in the locker and went to the pound to burn his mask and gloves that were used during the robbery; while doing so, one of the turtles swallowed the key to the locker. Nihonmatsu is later arrested by the authorities.