The episode opens with the group walking along a path through the forest when suddenly a Wurmple drops down in front of May, frightening her. Ash scans it on his Pokédex and Max comments that it can evolve into Beautifly. May decides to catch it and runs off. The others then chase after her.
The group catch up to May and then discuss May's plans. Brock then suggests that they stop for lunch, but May runs off alone to catch a Wurmple. In the bushes nearby Team Rocket are listening in, and decide that they will catch a bunch of Wurmple, and send one to the Boss, using the others to win all the Contests.
While walking through the forest, May comes across a group of Bellossom dancing. While she watches them, Team Rocket are looking for Wurmple nearby. James pushes gently on a tree to see if there are any Pokémon hiding in it, but Jessie tells him to do it properly, giving the tree a big kick. A Weedle falls out, so Jessie gives it another kick, making a Kakuna fall out. While Jessie gives the tree repeated kicks, James and Meowth ponder their find, commenting that Weedle evolves into Kakuna. They realize that Kakuna evolves into Beedrill just as they are surrounded by a swarm of angry Beedrill. May hears their screams and looks around to see Team Rocket running towards her. They tell her to run as they race past. She then notices the swarm and takes off. They escape when they fall down a small bank and the Beedrill fly straight past.
Team Rocket then perform their motto, but May notices a Wurmple and runs off before they can finish the first line, angering them. Both groups run after the Wurmple, and May sends out her Torchic, while Jessie sends out her Seviper. The two groups argue over who gets to catch Wurmple, until Jessie makes James send out his Cacnea. Both Pokémon gang up on Torchic, but then a Heracross comes out of nowhere and stops them in their tracks. The Heracross's Trainer approaches and comments that two on one isn't fair. Team Rocket retaliate by ordering both of their Pokémon to attack Heracross, but he orders it to use Fury Attack, blasting them off. The Trainer then introduces himself as Franklin and offers to help May catch a Wurmple, to which she agrees.
Brock places a pot of stew over a fire to cook while Ash and Pikachu practice Iron Tail. A Trainer then approaches, and suggests they battle, also introducing himself as Franklin. While the other Franklin and May climb a rocky cliff, Franklin explains Double Battles to Ash. He says that they have been an accepted form of battling in Hoenn for as long as he could remember. Ash accepts the challenge.
After Brock calls out the rules for their battle, Franklin sends out Yanma and Ariados and Ash sends out Treecko to join Pikachu. Both sides stare at each other until Brock starts the battle. Ariados uses String Shot, which is dodged, and then Yanma uses Sonic Boom. Ash tells Treecko and Pikachu to dodge, but as Pikachu dodges it is snared by String Shot. Ash tells Treecko to help Pikachu out, getting it out of the way just in time. Ariados and Yanma use Night Shade and Swift respectively, and both Ash's Pokémon dodge repeated attacks before Pikachu Thunderbolts Yanma. However, as it lands from the attack, it is struck with a direct hit from Night Shade, but Treecko reduces the damage by bumping Pikachu out of the attack. Ash then tells Treecko to use Quick Attack, forcing Franklin to focus his attacks on Treecko. Treecko dodges, allowing Pikachu to use Iron Tail on Yanma. Pikachu then tries to use it on Ariados, but it fails, and Pikachu is knocked away by String Shot. Treecko then uses Pound on Ariados, sending it flying into Yanma, who was still recovering from Iron Tail. Both Ariados and Yanma faint, causing Brock to declare Ash the winner. Franklin and Ash both check that their Pokémon are O.K., and congratulate them for the battle. Brock offers Franklin some stew.
May and the other Franklin are still looking for a Wurmple, when May brings back some Pecha Berries. Franklin then spots a Wurmple, so May sends out Torchic, which attacks Wurmple, and then May throws a Poké Ball at it, however Wurmple breaks out of the Poké Ball. Franklin suggests that Ember would be a good attack to use so, after an Ember from Torchic, May catches Wurmple. However, when she celebrates, Team Rocket use a grabber to snatch it from her hand. Team Rocket do their motto and then retrieve the Ball from the grabber. Franklin then sends out Heracross, which uses Horn Attack to pop their balloon, making Jessie drop the Ball. May runs after it and catches it, before Team Rocket send out their Pokémon again. Seviper starts to use Poison Tail, and Cacnea prepares to use Pin Missile. May tells Torchic to counter it with Ember, but Cacnea dodges and hits Torchic with Pin Missile. Heracross stops the Poison Tail by catching it and Franklin tells May to attack with both Torchic and Wurmple at the same time. May sends out Wurmple, but then realizes she doesn't know what moves it can use. Franklin suggests String Shot, which then completely immobilizes both of Team Rocket's Pokémon. Torchic's Ember then scores a direct hit, before Heracross's Megahorn sends them blasting off.
May runs up to the group to show them her new Wurmple, and notices that there are two Franklins. The Franklin that was with Ash's group introduces himself as Forrester Franklin, and his twin, who was with May, introduces himself as Forrest Franklin. Forrest reveals that he has decided to travel with his Pokémon, and then Brock suggests it is lunchtime. May releases her Pokémon so that they can eat as well, but Wurmple eats all of the Pokémon food and Brock's stew, before walking over to May and falling asleep.
Team Rocket are hanging onto a tree branch on the side of a cliff. They start arguing, but stop when Meowth notices a Wurmple at the end of the branch. Jessie throws a Poké Ball and catches it, but as she retrieves the Ball, Wobbuffet pops out of its Ball, causing the branch to break from the weight, sending them plummeting.