Ash and co. are traveling on Mr. Briney's boat to Dewford Island. They are enjoying themselves because of the fresh air and blue skies. Mr. Briney tells Ash that they should be at Dewford Island in a few hours. Ash is glad because he will be able to battle the gym leader by the next day. May sends out Torchic and Wurmple. She tells her friends that the Pokémon shouldn't miss out on the fun too. Ash and Brock think it's a great idea, and they send out their Pokémon as well.

Meanwhile, Team Rocket is in their Magikarp sub. They are shouting out a chant, "We are the best above all the rest!" They are busy with catching up with Ash and co. Because they are falling behind, they start to pedal faster. Max asks May if she would go swimming with him. May thinks that swimming is a great idea. Mr. Briney tells them that he knows a great place to swim. Ash is a disappointed because they are losing track. However, when he sees Pikachu sleeping, he decides to take a break and enjoy himself. They begin to change course. Pikachu wakes up from its nap. Ash tells Pikachu that they are going swimming on a nearby island. He points to the island.

Brock checks his guide book for the island's name. When he can't find it, he asks Mr. Briney for the name of the island. Mr. Briney tells Brock that the island doesn't have a name, nor is it on any maps. The island is a secret island that Mr. Briney accidently found while he was on his boat. May quickly changes into her swimsuit and jumps into the water. Max also changes and jumps into the water with May. The two of them begin to splash each other with water. Ash and Brock decide to go in the water too. Torchic, however, doesn't want to go in the water because it's a fire Pokémon.

Suddenly, a scream comes from May and Max. A large group of Sharpedo have surrounded them. Mr. Briney sends Peecko in to help May and Max. May and Max each grab a hold of Peecko's legs. Peecko begins to fly in the air. The Sharpedo all jump up and try to hit May and Max. Ash tells Taillow to help Peecko. Max gets hit by one of the Sharpedo. His leg is bruised because of Sharpedo's Rough Skin trait. May and Max are finally brought on the boat. May finds out that a part of her new swimsuit was ripped. She gets angry with the Sharpedo. Brock checks out Max's leg and makes sure that it's okay. Ash looks up Sharpedo in his Pokédex.

Mr. Briney suggests they leave the island now that the Shapedo are there. The Sharpedo all begin to ram the boat. Pikachu uses Thunderbolt to weaken the Sharpedo. This gives them a chance to leave. At night, Brock prepares a special dinner for everyone. Mr. Briney compliments on Brock's cooking. They are all having a real good time, however three Sharpedo are in the ocean keeping a look out for Ash and co. The rest of the Sharpedo are probably sleeping in a place nearby. Brock notices something strange with the Sharpedo. He says that Sharpedo usually are independent Pokémon. However, this time they are in large groups. Ash suggests they just battle the Sharpedo off. Max tells him that there are too many Sharpedo to battle. Brock suggests they find the leader of the Sharpedo and battle it. If they can beat the leader, then the other Sharpedo might begin to turn their backs on the leader. Mr. Briney thinks it's a good idea.

Team Rocket's submarine emerges from the water. They are disappointed because they are in the middle of the ocean and haven't gotten anywhere. Jessie suddenly sees the island. They imagine lots of food and restaurants on the island. Suddenly, a Sharpedo comes up to them. It begins to ram their submarine. James is scared stiff because a whole group of Sharpedo surrounds Team Rocket. Jessie send out Seviper. Seviper uses Poison Tail on one of the Sharpedo. The attack works. The leader and the rest of the Sharpedo charge towards the submarine. They knock into it, and Team Rocket blasts off into the sky.

Ash and co. have made a plan to battle the leader. The group of Sharpedo are already in the water. Ash gets on a platform and goes water skiing on it. Taillow and Peecko are pulling the ropes. Ash gets the Sharpedo's attention and leads them away. The leader, however, stays behind. Mr. Briney, May, and Max begin to pull their ropes. A fence comes out trapping the leader. The leader rams the fence, causing May to lose balance and fall in the water. The leader swims towards May. Just before May is attacked, Brock sends out Lotad. May grabs on a nearby rope, and Max pulls her to safety. Ash jumps off the platform and meets up with the others.

Now it's time for the battle with Lotad and Sharpedo. Brock orders Lotad to use Water Gun. Lotad shoots a stream of water at Sharpedo. Brock tells Lotad to use Water Gun again. Lotad takes a look at Sharpedo. It does not attack Sharpedo again. Sharpedo just lays in the water.

Ash and co. take the Sharpedo near land. Brock begins to check the Sharpedo. He reports that the Sharpedo has been poisoned by another Pokémon, and now the poison is beginning to take effect. Max thinks a Tentacruel must've done it. Even though Brock isn't a real doctor, he will still do his best to try and take care of Sharpedo. Mr. Briney tells Brock that he is doing a good job and that Sharpedo will appreciate it.

At night, everyone except for Brock eats dinner. Brock is still busy taking care of Sharpedo. He begins to talk to Sharpedo. He tells it to stay strong and not let the poison beat it. The next day, Sharpedo wakes up. It sees Lotad and then it sees Brock. It realizes that Brock helped it heal.

Suddenly, Team Rocket's submarine comes out from the water. Two nets are shot out capturing Pikachu and Sharpedo. Team Rocket then says their motto. Brock orders Team Rocket to release Sharpedo because it is sick. Jessie tells them that Seviper's Poison Tail must've caused the poison. Brock is angry that Team Rocket is responsible for Sharpedo's sickness. He sees Lotad near the net. Lotad uses Razor Leaf on the net, freeing Pikachu and Sharpedo. Pikachu is about to use Thunder on Team Rocket, but then it stops. Ash tells Team Rocket to look behind them. They do, and they see the whole group of Sharpedo staring at them. Team Rocket gets really scared now. The Sharpedo attacks Team Rocket, and they blast off again.

Brock is glad that Sharpedo is feeling better. The Sharpedo all thank Brock. Brock is worried that the Sharpedo's Rough Skin trait may take effect, but it doesn't. Mr. Briney explains that once you made friends with a Pokémon, their traits may not affect you. Ash, May, and Max all feel a Sharpedo's skin, and it doesn't hurt at all. Brock is glad that he has made friends with Sharpedo. Mr. Briney brings Ash and co. to the port of Dewford Island. Then he leaves for Slateport City. Ash and co. wave goodbye to the Sharpedo.

English Official Summary

Ash and company are sailing toward Dewford Town, thanks to their new friends Mr. Briney and his Wingull, Peeko. Mr. Briney stops at a small island so that Max and May can enjoy a swim while everyone else and their Pokémon relaxes and soaks up the sun. All the while, Team Rocket is tailing the happy sea goers underwater in their Magikarp sub. Team Rocket is not the only thing following our heroes, though. A dark shadow is following the boat as it turns towards the island. When they get closer  to the island, May and Max dive in the water and begin swimming and splashing around. Suddenly Ash and Brock hear May and Max scream. The boat is surrounded by a group of Sharpedo! Ash and Mr. Briney send Peeko and Taillow to help Max and May. Both Max and May were hurt by the rough skin of the Sharpedo. Pikachu uses its Thunderbolt attack to ward off the Sharpedo long enough for Mr. Briney to dock the boat on the island. While Ash and company set up camp for the night, Team Rocket surfaces, complaining of hunger. The Sharpedo begin attacking their sub and Jessie sends Seviper after them. After one successful strike, the Sharpedo retaliate and send Team Rocket blasting away. The following morning, Ash tries to lure the group of Sharpedo away from the island, but the leader is not tricked. Brock challenges the leader using his Lotad and wins after just two attacks. Brock realizes the Sharpedo is poisoned and begins nursing it back to health, only to discover that it was Jessie's Seviper that poisoned it. Team Rocket attempts to steal Pikachu again, but is warded off by the gang's new found group of Sharpedo friends. The episode ends with everyone swimming happily with the group of Sharpedo, which, they discover, only have rough skin when threatened or are around enemies. Now it's off to Dewford to compete for a second Hoenn badge!

French Official Summary

En route vers l’Île de Myokara, Sacha et ses amis décident de s’arrêter pour une petite pause sur une île qui ne figure sur aucune carte. Mais, avant d’avoir pu profiter de ses plages charmantes pour surfer, ils sont attaqués par un groupe de Sharpedo ! Après avoir été poursuivis jusqu’au rivage, ils regardent, consternés, ces puissants Pokémon se mettre à monter la garde pour les empêcher de quitter l’île ! Pierre remarque que l’un des Sharpedo est beaucoup plus grand que les autres, et il imagine un plan qui sera sans doute leur seule chance de quitter l’île : s’ils arrivent à battre le Sharpedo meneur lors d’un combat, peut-être que les autres leur céderont le passage !

German Official Summary

Ash und die Gefährten segeln dank Hilfe von Kapitän Salzkopf und seinem Wingull Pecko gen Faustauhaven.

Italian Official Summary

Ash e il gruppo sono su una barca per Bluruvia, grazie all'aiuto dei loro nuovi amici, il sig. Marino e il suo Wingull, Peeko.

Portuguese Official Summary

Quando um cardume de Sharpedo ataca, Ash e seus amigos ficam presos numa ilha não mapeada!

Spanish Latin America Official Summary

¡Cuando un banco de Sharpedo ataca, Ash y sus amigos quedan varados en una isla!

Spanish Official Summary

De camino a Pueblo Azuliza, Ash y sus amigos deciden hacer una breve parada en una isla inexplorada. Sin embargo, antes de poder disfrutar de sus solitarias playas y surfear, les ataca ¡un grupo de Sharpedo! Después de que los acorralen hasta la playa, observan atónitos cómo estos poderosos Pokémon montan guardia en el agua para que no puedan salir de la isla. Al ver que uno de los Sharpedo es mucho más grande que el resto, Brock idea un plan que podría ser su única oportunidad para escapar de la isla desierta. Si consigue derrotar al líder Sharpedo en combate, tal vez el resto de su ejército se disgregue.

English Great Britian Official Summary

Ash and company are sailing toward Dewford Town, thanks to their new friends Mr. Briney and his Wingull, Peeko. Mr. Briney stops at a small island so that Max and May can enjoy a swim while everyone else and their Pokémon relaxes and soaks up the sun. All the while, Team Rocket is tailing the happy sea goers underwater in their Magikarp sub. Team Rocket is not the only thing following our heroes, though. A dark shadow is following the boat as it turns towards the island. When they get closer  to the island, May and Max dive in the water and begin swimming and splashing around. Suddenly Ash and Brock hear May and Max scream. The boat is surrounded by a group of Sharpedo! Ash and Mr. Briney send Peeko and Taillow to help Max and May. Both Max and May were hurt by the rough skin of the Sharpedo. Pikachu uses its Thunderbolt attack to ward off the Sharpedo long enough for Mr. Briney to dock the boat on the island. While Ash and company set up camp for the night, Team Rocket surfaces, complaining of hunger. The Sharpedo begin attacking their sub and Jessie sends Seviper after them. After one successful strike, the Sharpedo retaliate and send Team Rocket blasting away. The following morning, Ash tries to lure the group of Sharpedo away from the island, but the leader is not tricked. Brock challenges the leader using his Lotad and wins after just two attacks. Brock realizes the Sharpedo is poisoned and begins nursing it back to health, only to discover that it was Jessie's Seviper that poisoned it. Team Rocket attempts to steal Pikachu again, but is warded off by the gang's new found group of Sharpedo friends. The episode ends with everyone swimming happily with the group of Sharpedo, which, they discover, only have rough skin when threatened or are around enemies. Now it's off to Dewford to compete for a second Hoenn badge!

Russian Official Summary

На пути к острову Дьюфорд, Эш и его друзья делают небольшую остановку чтобы поплавать. Они подвергаются нападению стаи Шарпедо. Брок озадачен, ведь обычно Шарпедо путешествуют в одиночку. Среди Шарпедо есть явный лидер, и наши герои понимают, что если им удастся его одолеть, другие не посмеют нападать. Когда начинается битва, Шарпедо ослабевает, словно отравлен. Брок день и ночь напролёт выхаживает больного Шарпедо. Появляется Команда Р, оказывается именно яд Севайпера отравил вожака Шарпедо. Вся стая Шарпедо преследует Команду Р и становится друзьями Эша и всей компании.

Dutch Official Summary

Wanneer een school Sharpedo Ash en zijn vrienden aanvalt, stranden ze op een onbewoond eiland!

Danish Official Summary

Da en flok Sharpedo går til angreb, strander Ash og hans venner på en uudforsket ø!

Swedish Official Summary

När ett helt stim med Sharpedo går till attack, blir Ash och hans vänner strandade på en outforskad ö!