Cheers on Castaways Isle! (Japanese: ピカチュウ・ポッチャマ漂流記！ The Pikachu-Piplup Drifting Chronicle!) is the 8th episode of Pokémon: DP Galactic Battles.
Piplup and Pikachu got stranded on a deserted island. This is due to events that happened some hours ago. As they were going away from Iron Island, Dawn and Ash do not see Piplup or Pikachu on the boat and go to search for them. Piplup is playing in the deck off the boat, though Pikachu warns him it is dangerous. Jessie, disguised as a noblewoman, has found Piplup and goes away, while James gets Pikachu. When the heroes came atop the boat, they see Team Rocket got them. Though they escape into the submarine, Ash sends Buizel and goes with it to get to Team Rocket. Suddenly, Team Rocket went in a current and it gets too strong, as Pikachu and Piplup get separated from the submarine.
Ash and Buizel go on the surface and are escorted by Officer Jenny back to the ship. Jenny tells the Captain when they get Piplup and Pikachu, Ash, Brock and Dawn will come back to the ship, then leaves. Piplup got Pikachu on the island, but is hungry, so Pikachu goes to get some food. Pikachu spots a group of Nosepass and Probopass, but passes near them and gets some apples. He comes back to Piplup, who eats each one in one gulp. This brings to the current event, where Pikachu and Piplup yell for help. Pikachu has an idea – he could use Thunderbolt and the ship should notice that and come over here. Piplup and Pikachu use BubbleBeam and Thunderbolt, but feel exhausted. They try once more, but a thunder from a cloud hits them. It begins to rain, so they go to find shelter.
Jenny thinks they have gone to the island near Diablo's Ocean, as due to a large amount of rocks, many boats find themselves destroyed when passing through the area. Ash sends Buizel and Staravia, to scout the island. Pikachu and Piplup see a group of Mantyke carrying some rocks and spot a Corphish gets them and places them near a gem. The gem glows and levitates a bit, but is dropped into the same spot. When it stopped raining, Corphish tells Pikachu and Piplup one day there was something flying and got struck by lightning. It transformed into the glowing gem and landed on that spot. When it transformed into the gem, one rock shined brightly and with the Mantyke, it began collecting them and putting them near the gem.
To help them, Pikachu and Piplup go to smash some rocks and bring it to the gem. Pikachu goes to use Thunderbolt, but Piplup warns him he would electrocute everyone, so Piplup uses BubbleBeam to crack some rocks. Pikachu spots a big boulder and goes up and dives, using Iron Tail to bring the boulder down. As they go back, Staravia and Buizel see Pikachu and Piplup and go back, reporting to their master what they saw. Pikachu and Piplup brought the rocks to the gem and it begins to absorb the energy, but Team Rocket arrive and the gem stops absorbing. Team Rocket launches a hand to get Pikachu and Piplup, but Corphish uses Crabhammer to destroy the arm. Team Rocket launches another arm, but this one is made of gold, so Corphish is bounced back and Team Rocket gets Piplup and Pikachu.
However, Staravia's Aerial Ace and Buizel's Water Gun free Piplup and Pikachu, while, Ash, Brock and Dawn come to them. Jenny tells Team Rocket they are arrested, but then, the gem begins to glow and a Deoxys comes out. The Deoxys absorbs more rocks, which are actually meteors. Jenny goes away, as her boat is being attracted, while Team Rocket's submarine levitates to it. Jessie sends Yanmega, who goes to attack Deoxys, but Deoxys hits Yanmega, pushing it to a boulder to the submarine and causing Team Rocket to blast off.
The meteors fall on the gang, so Deoxys smashes some of them and protects the heroes from more meteors. Everyone thanks Deoxys and waves goodbye, as it goes into the sky, towards the Aurora Beam. The gang thinks that many more mysterious Pokémon exist they have not yet seen or met. Still, they are happy to know that they are near Chocovine Town, where they need to be for Dawn's next Contest.
- Professor Oak's Pokémon lecture: Numel
- The Probopass standing still on the island might be a reference to the moai statues of Easter Island.
- Pocket-ering Monster-ing can be heard in the Japanese version.
- This episode is included on the Pikachu's Ice Adventure DVD.
- The dub title may be a reference to the last line of Ballad of Gilligan's Isle, the theme song for Gilligan's Island. That line is Here on Gilligan's Isle.
- This is the second time a Mantyke has looked after a helpless Pokémon. The first time was caring for the Manaphy Egg in Pokémon Ranger and the Temple of the Sea.
- Early in the episode, when Ash and his friends are seen walking through a corridor in the ship, the Poké Ball design on his hat turns blue-green.
- In the episode, the meteorite is referred to as a "meteor", which is incorrect. For an object to be a meteor, it must still be burning up in the atmosphere - once it has landed, it is referred to as a meteorite.
- When this episode was broadcasted in Finland's MTV3, the opening sequence had the instrumental version of Battle Cry playing.