Lana and Popplio are working hard to master their Z-Move, but their progress is soon to grow by leaps and bounds!

Our heroes are having a sleepover at Professor Kukui’s house, and Professor Burnet agrees to join them! Everyone has a good time, but there are a couple of hiccups: during a game of Z-Move poses, Kiawe accidentally unleashes Turtonator’s Inferno Overdrive in the living room, and then Professor Burnet’s Munchlax eats everything she cooked for dinner!

That night, when Lillie has trouble sleeping, she talks with Professor Burnet, who offers some advice about her family. The next day, Nebby unexpectedly whisks her away to visit her brother—and his partner, the mysterious Silvally, who leaves her terrified and apparently unable to touch Pokémon again!

When Harper and Sarah tell Lana that a Pokémon saved them after they got lost in the woods, Mallow remembers the same thing happened to her and Lana when they were younger! The two friends decide it’s time to find this Pokémon, nicknamed Grandpa Forest, and offer it their thanks. Always up for an adventure, Ash and Pikachu tag along, too! Our heroes soon learn that Grandpa Forest must be a Drampa, and when they find its favorite bittersweet Haban Berry trees, they realize they’re on the right track. Then, after a brief scuffle with Team Rocket, Lana and Mallow joyfully reunite with their old friend!

There’s plenty of excitement at the Pokémon School when Ilima, one of its most skilled graduates, returns for a visit. The students have heard plenty of stories of Ilima’s adventures with Eevee, and after sharing those stories with Ash and Lillie, they want to learn if the legends are true. Despite that popularity, though, Ilima’s reappearance has attracted the unwanted attention of Team Skull’s Tupp and his crew of Grunts.

After James’s Mareanie masters a Dark-type move, Team Rocket realizes that they can finally take advantage of their Dark-type Z-Crystal. To this end, the Boss sends them to Ula’ula Island to get a Z-Ring from the kahuna—but they accidentally unleash a greedy Gengar who steals their Z-Crystal and kidnaps a girl named Acerola! Team Rocket sets off in pursuit, but can they defeat the ghostly thief? And just what are Gengar’s true intentions?

On their way to the ferry back to Melemele Island, our heroes take a shortcut through a cave. They find an area filled with luminescent moss, and Kiawe’s overexcited Marowak starts a commotion that separates everyone into groups. While the others try to find their way out, Lillie, Sophocles, and Mallow discover a group of Alolan Sandshrew in training. The Sandshrew are threatened by a Tyranitar, but Lillie intervenes. She challenges Tyranitar to a Double Battle—and wins with the help of Snowy and the Sandshrew Boss! To show their gratitude, the Sandshrew present Lillie with her very own Icium Z!

The Ultra Guardians are beside themselves with excitement, as Lusamine has booked them a day at the Pokémon Paradise Resort—and the hardworking Ride Pokémon are tagging along, too! Everyone enjoys the spa’s relaxing amenities, but Team Rocket shows up in disguise with other plans: stealing all the Pokémon they can! Fortunately, the Ride Pokémon have none of it, and they make sure to dash the troublemakers’ ambitions. Our heroes finish their spa day in total luxury, while Team Rocket ends up stuck in the mud with Bewear...

Harper and Sarah are determined to visit a haunted house, but when our heroes are stumped as to where to find one, Acerola suggests they create their own! At first, Shuppet and Mimikins provide ghostly entertainment for the twins, but then several other Ghost-type Pokémon join in on the fun. Everyone gets caught up in what looks like a scary dream, but when Komala strikes the Pokémon School bell, they all wake up and breathe a sigh of relief! Still, Lana is not amused with her sisters’ rambunctious behavior…

As our heroes prepare for a break from Pokémon School, Lana makes a surprise announcement: they have visitors! Who? None other than Misty and Brock! Everyone’s excited to show Ash’s longtime friends around Alola, and when Ash tells them about Treasure Island—a place he and Pikachu previously visited—they’re off! They meet up with a group of Mantine who love to surf, but Team Rocket is determined to make a splash—by catching the Mantine and Pikachu! But they’re no match for our heroes, who shower the trio with a series of attacks that send them blasting off again…just like old times!

After a ship's captain reports being saved by a Dragonite, Goh and Ash set out in search of the Dragonite island that they believe exists ... somewhere.