Arriving at the seaside Ambrette Town while traveling to Cyllage City, our heroes are basking in the wonderful ocean breezes. Ash wants to train there with Froakie, but Serena has another idea: pay a visit to Ambrette Aquarium! Everyone agrees, and they marvel at the vast number of Water-type Pokémon there. They also meet a gentleman who tells them a little about the aquarium and shows them a statue of a golden Magikarp. He also directs them to the aquarium’s curator, Rodman, who’s fishing on the beach with his rather prickly Clauncher.

Rodman tells our heroes a local legend about a golden Magikarp who once rescued a diver in danger, and says he’s trying to catch it for the aquarium so everyone can see it! Ash, Serena, and Clemont want to help him catch it, and he happily hands out fishing rods. Of course, Team Rocket has been listening in on the conversation, and the villains want to catch the golden Magikarp for themselves...

No one is having any luck, so Clemont produces an invention to lure Magikarp in toward the shore. It’s not quite as fine-tuned as Clemont hoped, instead attracting several cranky Sharpedo. Not to be defeated, Clemont reveals yet another invention, determined that this next one will work right. And sure enough, all the fishing rods get a bite at the same time, and with a mighty effort, our heroes and Rodman reel in their catch—and it’s a golden Magikarp! Unfortunately, this one is Team Rocket’s new submarine, which they designed to fool the real golden Magikarp.

After they send Jessie, James, and Meowth blasting off again, our heroes and Rodman are ready to call it a day. But just as they’re about to leave, a magnificent golden Magikarp leaps out of the water! Rodman is delighted to learn that the old story was really true, and promises our heroes that the next time they visit his aquarium, the golden Magikarp will be part of the exhibit!