As they have been constantly having to assemble to take on the Ultra Beasts that appear in Alola, Ash & Co. are taken to a Pokémon Steam Paradise resort, where they also take their Ride Pokémon in order to get some rest. However, while relaxing, Team Rocket soon appear and kidnap various Pokémon. Will Ash & Co. be able to stop them?

Lunala and Necrozma have appeared at the Altar of the Sunne and start battling. Ash & co. start to try to battle Necrozma to help Lunala but their attacks have no effect. However, to make things worse, a group from Team Rocket have also appeared and are trying to catch both Lunala and Necrozma. When all seems to be useless, Nebby returns from the Ultra Wormhole. What will happen? Will they be able to stop Necrozma and Team Rocket?