Ash and co. head for the Indigo Plateau, the place where the Grand Festival will be held. Ash wants to do some serious training upon arrival of Indigo Plateau. May is feeling really confident for the Grand Festival. Max warns May to be careful since all of the greatest coordinators will be competing. May takes out her ribbon collection and admires it. She really hopes to win the festival.
Suddenly, they see a man chasing a group of Aipom. It appears the Aipom have stolen some food. The Aipom jump over Ash and co. One Aipom steals May's ribbons, and another Aipom steals Ash's hat. Now Ash and co. are angry, and they begin to chase after the Aipom too. The Aipom escape through the bushes. May wonders what she will do without her ribbons. The man walks up to them and hopes they are okay.
Everyone walks back to the man's house. The man's name is Taylor. He tells Ash and co. that he was gathering some berries for Pokeblock when the Aipom stole them. Ash and co. introduces themselves to Taylor. Taylor tells them all that the Aipom used to only take berries off of his trees when they were hungry, however things are different now. Outside, all of the trees are left bare. Taylor explains that other Pokémon besides the Aipom have been taking food from him. This also didn't start until a few short days ago. Taylor tells a story about how a lost traveler saw a giant monster. For some reason, the Aipom are taking the berries back to the mountain. May needs to get her ribbons back, and Ash needs to get his hat back. Taylor also wants to see the monster, so they all decide to go to the mountain.
The Aipom approach Meowth and Wobbuffet (they are in disguises). The Aipom bow down to them, and they give them the berries. Meowth accepts the berries, and the Aipom run off. Meowth brings the berries to their stash. Jessie and James jump out. James notices that they have tons of berries to make lots of Pokeblock and auction them off at the Grand Festival. Jessie notices the ribbon case. She opens it up and sees five ribbons in it. James tells Jessie that the ribbons aren't hers, but Jessie ignores him.
Ash and co. run up towards the place where the monster is at. While they are running, they see a group of Mankey with berries jumping by. The Mankey and other Pokémon approach Meowth and Wobbuffet. They give their berries to them. Ash and co. are hiding behind the bushes and watching them. The gate begins to open, and Meowth and Wobbuffet head inside. The shadow of the monster is seen. May wants her ribbons back. Before the gate can fully close, Ash and co. run out and onto the other side of the fence. May demands Meowth to give her ribbons back. Jessie and James walk out. Jessie is holding May's ribbons and her case. May wants them back, but Jessie doesn't give them back. Ash knows that Team Rocket is up to something. Meowth says that they are just supporting the mountain king which happens to be a giant Slaking. The gate opens and the other Pokémon peek inside. Meowth tells the Pokémon that the mountain king wants them to get rid of Ash and co. The Pokémon begin to chase Ash and co. out of the place.
Ash and co. run up the mountain. More Pokémon come out, and they block Ash and co.'s path. Ash tells Pikachu to use Thunderbolt. Pikachu fires the electricity at the ground to scare off the Pokémon. Taylor thinks they should all split up. Ash and Brock will go one way while Taylor, Max, and May go another way. The Pokémon regroup, and they split up too. The Aipom chase after Ash and Brock. Brock lays out some Pokémon food to distract all the Aipom except for the one with Ash's hat. Ash and Brock come to the edge of a cliff. The Aipom jumps onto Ash's head. Ash falls off the cliff along with the Aipom. He grabs onto a tree branch and the Aipom. The tree branch breaks, and Ash and Aipom land in a few bushes. Ash's hat has fallen off of Aipom. Ash and Aipom run to get Ash's hat. Aipom manages to get Ash's hat first.
Meanwhile, the Mankey, Vigoroth, and Slaking are looking for Taylor, May, and Max. Taylor, May, and Max have hid in the trees to avoid the Pokémon. Even though they were lucky, May still has to get her ribbons back. Taylor and Max have agreed to help May. Ash places his hands in the water to wash his face. Aipom stands right next to Ash. Ash notices that Aipom still has his hat. Then Ash tells Aipom not to believe a single word Team Rocket says since they are always doing bad things. Brock and Pikachu catches up with Ash a few seconds later. Ash and Brock tell Aipom that they have to leave. They run off leaving Aipom behind.
Ash and Brock discuss what they will do once they arrive at the gates. Ash assumes that Team Rocket also tricked the giant Slaking, so they have to stop them. The giant Slaking has just consumed all the berries. The giant Slaking lends its hand down to put Team Rocket on its shoulders. Suddenly, Taylor, May, and Max use ropes to climb over the fence. May demands to have her ribbons and all the berries back. Jessie holds out the ribbon case and teases May. The giant Slaking begins to walk towards May. May sends out Combusken. Combusken uses Fire Spin, but the Slaking blows out a gust to kill the fire. Then the Slaking breaks the fence and escapes.
Ash and Brock arrives. Pikachu uses Thunderbolt to slow down the Slaking and Team Rocket. May tells Ash and Brock that Jessie still has her ribbons. Team Rocket says their motto. Team Rocket wants Pikachu. Slaking reaches down and grabs May. Then the Slaking begins to climb a small hill. Jessie tells Ash and co. to give them Pikachu or else May will get hurt. Ash sends out Swellow to save May. Swellow swoops around the Slaking. The Slaking gets angry and drops May. Ash sends out Sceptile. Sceptile dives for May and catches her. Swellow then hits Slaking with Aerial Ace. Slaking and Team Rocket fall off the hill. Then Combusken uses Fire Spin to burn Team Rocket. Afterwards, Marshtomp uses Water Gun to douse out the fire. When the fire is gone, a metal Slaking is shown. Apparently, the Slaking was just one of Team Rocket's robots all along.
All of the other Pokémon arrive. They now understand that the Slaking was just a robot and not a mountain king. The Pokémon are angry at Team Rocket for tricking them. They begin to attack the robot. Aipom uses their Scratch attack while some of the other Pokémon throw things at the robot. The robot becomes seriously damaged that it breaks. The robot falls to the ground, Team Rocket is thrown out, and the berries are released from the robot's insides. Ash demands that Team Rocket gives the berries back, and May wants her ribbons back too. Jessie holds out May's ribbons and refuses to give them back to her.
Jessie sends out Seviper. Seviper uses Bite, but Combusken counters with Quick Attack. Seviper uses Bite again, but Combusken dodges and hits Seviper with Sky Uppercut. Seviper crashes into Jessie, and the ribbons fall out of Jessie's hands. Now it is James's turn to battle. He sends out Cacnea. Cacnea uses Needle Arm. Pikachu uses Volt Tackle and hits Cacnea. Cacnea falls back into Team Rocket, causing them to blast off again.
Taylor thanks Ash and co. for saving the day. He wishes May the best of luck at the Grand Festival. Ash and co. wave goodbye and begin to head towards the Grand Festival. Ash wished he had his hat back. Sitting on a rock is Ash's hat. Ash can't believe his luck. He picks up his hat and places it on his head. They wonder how the hat got back on the rock. Realizing that it was Aipom, Ash thinks that Aipom is a cool Pokémon.
