In the misty mountains of Izabe Island, Ash and friends spot a giant Pokéball atop a mountain. They wonder how it got there as a man appears behind them. The mist dissipates and the man introduces himself as Sigourney: Sage of Izabe. He offers to tell them the tale of the Pokéball on one condition: they buy souvenirs. They end up buying some and Sigourney begins the story.

Long ago, a giant Pokémon attacked Izabe Island. And it was finally stopped by the White Sage who threw a giant Pokéball and captured it. Currently, the Pokéball rests at the bottom of Izabe Lake. Up above, Team Rocket rests on a cliff listening to the whole story. Not surprisingly, they decide to steal the Pokémon inside for their own.

They fly over to the lake in their balloon and arrive just as Ash and friends arrive with Sigourney. Ash calls them crooks who steal things. From the balloon, Team Rocket contradicts Ash’s statement. They proceed to say their motto and drop bombs on the Pokéball below them. A huge hole appears in the top of the Pokéball and a white light shines from within. As Team Rocket’s balloon floats to the side, the lake parts in the middle to give room to the giant Pokémon as it appears.

Once it fully materializes, everyone sees that it is a giant Claydol. Sigourney reads from his book that a normal Claydol could fit inside one of the giant one’s eyes. Ash whips out his Pokédex and quickly looks it up. Team Rocket’s balloon has now floated back above Claydol and they drop a net on it. Claydol doesn’t like the net and fires an Ice Beam at Team Rocket. It then blasts them off with Hyper Beam. Due to their location, after blasting off, Jessie, James and Meowth come straight back down from the sky and land on top of Claydol who begins to leave the lake area and head in the general direction of town.

Ash sends out an empty Pokéball in an attempt to catch the oversized Pokémon but it easily breaks free. Sigourney reads from his book that the White Sage attacked Claydol with a Water Pokémon so Brock sends out Mudkip and Lombre to help and has them fire Water Guns at Claydol. The attacks don’t even faze the giant beast; it uses Rapid Spin to send the attacks back at the group gathered on the cliffside. Both Water Guns hit a spot just above them on the cliff and create a huge hole in it. Team Rocket flies off Claydol and lands behind everyone. They have a short meeting together and agree to help “the twerps” defend the town from Claydol in an attempt to steal the Claydol.

Sigourney reads in his book that the Claydol loves eggplant. So, Ash and James use a huge fishing line to wave a basket of eggplant in front of Claydol. However, the Pokémon ignores the food. As “Plan B,” Ash and James dress up as eggplants to lure the Claydol away from the town. It works… until Sigourney reads that Claydol hates eggplant. May quickly warns Ash and James to get away from Claydol and they escape from the costumes just before Claydol begins pounding them.

With the eggplant costumes smashed and torn on the ground, Claydol continues its journey towards the town. Sigourney continues reading from the book and determines that a beautiful maiden lured the Claydol away from the town. So Jessie, May, Meowth and Wobbuffet dress up as maidens. When that doesn’t work, Jessie switches to a ballerina outfit, May to a nurse, Meowth to a cheerleader and Wobbuffet to a maid complete with feather duster.

Claydol notices them and begins attacking them one by one. Jessie is sent away with a Hyper Beam. Then, Meowth is blasted with an Ice Beam and finally May is thrown away with Psychic. Sigourney consults the book again and determines that the maiden might have been ugly and that would be the reason Claydol went after Wobbuffet.

Down in the valley, Claydol chases Wobbuffet. Wobbuffet is told to lead Claydol past the base of the mountain. Meanwhile, everyone else goes to the top of the mountain to push the giant Pokéball down to capture Claydol once more. While running, Wobbuffet’s wig comes off and Claydol becomes confused. Wobbuffet runs past the mountain with Claydol following and Brock gives the signal to send the Pokéball down.

Everyone pushes with all their strength and the Pokéball begins to roll down the mountain. On the way down, the Pokéball gets stuck on a rock but Mudkip, Lombre and Pikachu quickly destroy the rock and the Pokéball continues down.

Just as Claydol is passing the base of the cliff, the Pokéball captures it. Returned to their evil states of mind, Team Rocket tries again to steal the Claydol but the Pokéball is too heavy for the balloon to carry and Team Rocket is dragged down the mountain path, which circles the mountain several times before going to the lake. The Pokéball ends up in the lake, where the other Pokéball originally rested.

That night, the Pokéball rests peacefully as Ash, Brock, May, Max and Sigourney watch the sun set over Izabe Lake.