Back on Melemele Island after completing their Poni Island research projects, our heroes are unaware that some small, mysterious Pokémon have hitched a ride with them. As they soon discover, these Pokémon love to eat metal—including the tools the Pokémon School class needs for today’s lesson, as well as Team Rocket’s supplies and James’s prized bottle cap collection! Rotom Dex is excited to compile vast amounts of data on this new kind of Pokémon, and Ash relays the information to Professor Oak—who says this mystery Pokémon may indeed be one amazing discovery!