Hau and his partner Dartrix are training hard for the island challenge when they have a run-in with Ash and Rowlet. When Ash learns that Hau’s grandfather is Kahuna Hala, he challenges his new friend to a battle! Dartrix wins easily, but Rowlet is fired up, and at a suggestion from Professor Burnet, Ash decides to teach it a new move. Returning to the woods where they first met, they encounter Trumbeak and Toucannon, who try to teach Rowlet to use Bullet Seed. That isn’t a move Rowlet can learn, but with determination, it does master Seed Bomb (after swallowing an Everstone)—and in the rematch, Rowlet emerges victorious!

Today is the sole performance of the Pokémon School play, and everyone’s so excited! Lillie stars as Lillier, a brave adventurer who is charged with restoring Alola’s lost energy using a staff imbued with the power of Legendary Pokémon. But Act Two takes an unexpected turn, as Jessie, in disguise as Jessa Bergère, crashes the performance to steal the spotlight for herself! After some confusion, Rotom Dex writes a magnificent new script on the fly, bringing the crowd (including Ash’s mom) to applause for a job well done!

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…

The Ultra Guardians have been summoned to investigate unusual magnetic activity around Wela Volcano, where they discover a group of Alolan Geodude and Alolan Graveler munching on Spark Stones. But our heroes also find a group of rock hunters who are after the Spark Stones for themselves. The Ultra Guardians spring into action…but so does an enraged Alolan Golem, who sends the rock hunters packing! Thanks to the efforts of Sophocles’s friend Metang, the Golem eventually calms down—and it happily joins a group of Hikers who promise to keep watch over the volcano!

Ash heads to Aether Paradise to deliver the lunches Professor Burnet and Munchlax forgot at home, and he and Lillie enjoy seeing the Pokémon there. But Team Rocket is there, too, plotting to steal Pokémon while in disguise as Aether Paradise employees. When one of the Pokémon from the conservation area, an adorable Stufful, goes missing, everyone suspects Team Rocket of foul play. But Stufful refuses to leave Team Rocket’s side, and when Bewear appears to whisk them away, everyone learns that Bewear and Stufful are family! This time, Team Rocket’s exit includes a new member of the group: Stufful!

When Rotom Dex catches a continuity error during the filming of Alolan Detective Laki, the cast and crew are so impressed that they invite it to join the show and help Laki solve cases! Ash is thrilled, until he realizes the international shooting schedule means Rotom will have to leave… While our hero sadly considers this option, a serious conversation with Laki reminds Rotom that its real dream is to be the best Pokédex in the world—and when Ash tries to be strong and send his friend off to pursue an acting career, it decides to stay and study rare Pokémon with him instead!

A familiar Eevee has been making its way across the ocean toward Alola, and its journey has been filled with adventure. A series of harrowing encounters—including a brush with Team Skull—has tested its determination, but when it finally finds our heroes, it’s as happy as can be! After forming a bond with Popplio, Eevee’s ready to join Lana’s team…but not before Lana gives it a name: Sandy! Lana and her family are thrilled to get to know her new partner—and Sandy’s excited to get to know them, too!

While battling Tapu Koko, Ash and Pikachu suddenly find themselves in an unfamiliar place inhabited by a menacing Ultra Beast known as Guzzlord! Guzzlord’s power is fearsome, but a mysterious man named Dia—accompanied by the Mythical Pokémon Zeraora—comes to our heroes’ aid. Ash wants to help Dia reclaim his home from Guzzlord’s destructive wrath, but after Dia defeats Ash in a test battle, our hero relents. He and Pikachu must return to their own home, but how? Dia offers them shelter for the night, but on the way, they discover an abandoned Pokémon School! What could all of this mean?

After traveling to an unfamiliar place, Ash encounters the Pokémon School in ruins. The mysterious Dia explains that Ash must be from a parallel world, where the Alola region hasn’t been destroyed. After convincing Zeraora to help Pikachu train, Ash teams up with Dia to force Guzzlord back to its own world through an Ultra Wormhole. Zeraora and Pikachu use powerful attacks against Guzzlord’s weak spot, but it isn’t enough. Then, the parallel world’s Tapu Koko appears and enables them to use their Z-Moves again, and it works! Guzzlord is banished, and for the first time, Dia sees hope for his world as Ash returns to his own.

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!

Brock and Misty are having quite a busy vacation in Alola! Ash and the Pokémon School gang admire Brock’s culinary skills, boosted by delicious ingredients from Kiawe’s family farm. They decide to visit the farm on Akala Island—mostly because Brock has been determined to meet the beautiful Kahuna Olivia! Like many of Brock’s crushes, Olivia is taken aback…but the two are soon bonding over their shared love of Rock types, and when Team Rocket attacks, they respond with a paired-up Z-Move! Brock and Misty’s visit ends with a beautiful fireworks display and promises to return to Alola for more vacation fun!

The Pokémon School class is visiting Poni Island, and everyone is excited about their upcoming research projects. Ash wants to compete in his fourth grand trial, but because the island currently has no kahuna, he plans to challenge Tapu Fini instead! While searching for the Island Guardian, he meets a Trainer named Hapu, who impresses our hero with her tenacity and battling skills. Although Hapu doesn’t share Ash’s enthusiasm, she respects his determination. And when Team Skull tries to capture a group of Oricorio, she jumps into the fray and defeats the hapless trio with just one hit!

When Hapu learns that Ash wants to battle Tapu Fini for his Poni Island grand trial, she lectures him about the true meaning of a grand trial, and Mudsdale backs it up with a tremendous kick! Ash goes flying and lands near Gladion, who’s also come to challenge the Island Guardian. The two rivals decide to battle each other instead, in a Lycanroc showdown: Gladion’s Midnight Form versus Ash’s Dusk Form! Hapu reluctantly agrees to be the referee, and as the battle continues, she begins to understand Ash’s determination. After Gladion wins, Tapu Fini makes an appearance, and our heroes wonder if it will listen to their request…

As our heroes continue their research projects, Sophocles wants to help Charjabug evolve. The pair set off to Vast Poni Canyon and encounter Horacio, who wants his own Charjabug to evolve first. But when Horacio ends up in danger, Sophocles’s Charjabug springs into rescue mode and evolves into Vikavolt! Meanwhile, Lana has her heart set on training, but she’s disappointed because her mentor, Ida, is about to depart Poni Island. Still, Popplio and Sandy have fun playing with Ida’s Primarina, and when Lana decides to show Ida what she’s capable of, Popplio evolves into Brionne! As congratulations, Ida gives Lana her own Primarium Z and encourages her to continue training.

Ash and Kiawe set off to challenge Tapu Fini to a grand trial, but when they get no response, they decide to battle each other to attract its attention. When the battle gets out of hand and starts to damage the surrounding ruins, Ash finds himself trapped in an energy field as punishment, and a mysterious old man tells Kiawe he must return with a scale from Tapu Lele to rescue his friend. Kiawe completes his quest just in time—and when Tapu Fini appears and gives him a Z-Crystal, it becomes clear that this was Kiawe’s grand trial! Meanwhile, Mallow has been working with Hapu to develop new recipes using Poni Radishes. Two more research projects completed!

Get your tissues ready, because this episode of Pokémon the Series: Sun & Moon—Ultra Legends is a real tearjerker. On Poni Island, Hapu tells Ash and friends about a strange mist created by Tapu Fini. When people and Pokémon venture into the fog, they can be temporarily reunited with loved ones who have passed on. Ash, Mallow, and Hapu herself all encounter the mist, and when Lillie and Gladion emerge from it, a shocking revelation sets the stage for an exciting mystery!

Following her standing up to Tapu Fini, Hapu has finally become the Island Kahuna of Poni Island, and Ash challenges her to her Grand Trial. Her trial requires Ash to battle her with just one Pokémon. With Hapu using her Mudsale, Ash and Pikachi face a tough battle. Will they be able to win the Grand Trial and finish Ash's research project?

After their visit to Poni Island, Ash and the gang meet legendary Poké-golfer Kahili, who has been on a losing streak lately, and her partner Touckey (Toucannon). It's the first time that the gang has seen Poké-Golf, a sport that's popular in Alola, and are fascinated, so they ask Kahili to teach them how to play. In this version of Golf, both trainer and Pokémon must work together...will they do well and who is this self-proclaimed "Caddie Expert" who keeps butting in?

Some mysterious and unknown Pokémon have arrived on Melemele Island, and they eat metal! They start wreaking havoc across the island, including eating the tools at the Pokémon School, the equipment in the Ultra Guardians' headquarters and even James's precious bottle cap collection. James is enraged and decides to chase down the Pokémon to get his revenge. Just who and what are they and why is one of them hanging around Ash's Rowlet?

Professor Oak has finished his research on the mysterious new Pokémon Ash reported and names the new Pokémon Meltan, a Steel-type. One of the Meltan has grown attached to Ash's Rowlet and stows away in Ash's backpack with Rowlet to join them all at the Pokémon School, but after an incident with a Murkrow, it loses its Hex-Nut. Rowlet tries to replace it but nothing he tries seems to work, so he and Meltan head out to find its Hex-Nut. However, they run into Team Rocket, who have found Meltan's Hex-Nut and are still after all the Meltan. Will Rowlet be able to protect Meltan?

Sophocles is on a TV quiz show, so Ash and the gang come to the station to cheer him on. While there, they see the filming of a series starring a Magikarp; however, the Magikarp seems to have something wrong with it. On another TV show, the regular actresses don't show up in time, which leads to Lana, Mallow and Lillie being cast as replacements.

A new Ultra Beast, Pheromosa, has appeared and started attacking trainers and stealing their Z-Crystals. The Ultra Guardians are tasked with stopping Pheromosa. Pheromosa steals Team Rocket's Z-Crystals, but while trying to stop it Meowth falls in love with Pheromosa. Will anybody be able to stop it before it's too late?

After much planning, Professor Kukui has finally announced the formation of a Pokémon League in Alola. However, while the rest of Alola (including Team Rocket) celebrates and gets ready, Team Skull's leader Guzma is enraged and decides that he will destroy the new Pokémon League, and heads over to the Pokémon School to confront Kukui. Before things can get ugly, Ash challenges Guzma to a battle. It's Pikachu vs. Guzma's Golisopod; who will win, and why does Guzma hate Kukui so much?

Since their Poni Island experience made them realize that their father Mohn is still alive, Lillie and Gladion return to Aether Paradise and go through their father's papers, hoping to find some clues. Back at the family mansion, Lusamine shows them Mohn's old office, where Lillie discovers her father's old Z-Ring and the inoperative Mythical Pokémon Magearna. Lillie goes to Kahuna Hala and asks for permission to use her father's Z-Ring, and they have a battle to see if Lillie can master Z-Moves. Will Lillie and Gladion learn anything new about their father's whereabouts, and what is Magearna's connection to Mohn and Lillie?

Ash and the gang travel to picturesque Malie City on Ula'ula Island. When a strong wind blows Mallow's hair ornament away, Shaymin chases after it, followed by Sandy and Meltan. Unfortunately, Team Rocket, who are also in Malie City, spots the trio and goes after them to catch them, but our three adventurers aren't going to let themselves be taken without a fight!