Ash is flying on the back of the Legendary Pokémon Reshiram and having a great time! Suddenly, they are confronted by Iris, who’s riding the Legendary Pokémon Zekrom and challenging them to battle! Zekrom unleashes a fearsome Thunderbolt that knocks Ash right out of the sky...

...and into his bed at Professor Juniper’s lab. He’s been dreaming, and when Iris couldn’t wake him up, she asked Pikachu to use Thunderbolt on him. She tells him to go get ready, because the next part of their adventure starts today! Ash is planning to head home to the Kanto region, and Cilan and Iris both decide they want to come along! Professor Juniper suggests that they travel to Kanto on a cruise ship that stops in the Decolore Islands, an idea everyone seems to like...including three eavesdroppers from Team Rocket.

Thanks to some Team Rocket trickery, our heroes end up aboard their small ship instead of the one that’s actually going to Kanto. Jessie, disguised as a ship’s attendant, gets Ash, Iris, and Cilan to leave their Poké Balls with her, and invites Pikachu and Axew along for a snack. She locks the Pokémon inside the playroom while James (disguised as the captain) takes our heroes to their room and locks them in too.

But one Poké Ball rolled away while Jessie was distracted, so Oshawott is free to explore the ship—and it quickly discovers Team Rocket’s plot! Oshawott attacks, and its Razor Shell hits the control panel, knocking out power to the ship and unlocking all the doors. Ash, Iris, and Cilan quickly reclaim their Pokémon and head to the deck to confront Team Rocket! A battle begins, even though Cilan warns fighting on a ship probably isn’t a good idea. And he’s quickly proven right when Iris tells Excadrill to use Dig—and it digs right through the bottom of the ship, which begins to sink!

Team Rocket blasts off on a huge spout of water, and our heroes manage to escape, finding their way onto the right ship this time. It’s all aboard for Kanto by way of the Decolore Islands, as the adventure continues!