Conan stumbling into a mystery that mirrors his own Detective Boys but with the roles reversed, he's the adult now, they're the desperate ones, creates an uncomfortable echo that the OVA actually leans into. The missing kid isn't a puzzle to solve for fun; it's a reminder that Conan's trapped in a child's body watching real children face real danger. A single episode that does more to expose the cost of Conan's situation than a dozen case-of-the-week episodes ever could.

Conan and Ran travel to Osaka to visit Heiji and Kazuha, and while the four are sightseeing they meet a trio of children. The kids look strangely like the Detective Boys, though their personalities are different. They are searching for a friend who has gone missing, and Conan and Heiji agree to help track down the vanished boy in this one-episode mystery adventure OVA.