After earning the Dynamo Badge from Wattson, Ash and co. continue their journey. May insists to go to Fallarbor Town while Ash suggests they go to Lavaridge Town. Max suggests they go to both and Brock decides the order. During the trip they notice some watermelons float down by the river and have some lunch. Ash then comes up with an idea: Teach Treecko to use Bullet Seed like the Shiftry that attacked them a while back, and as practice they try it by spitting watermelon seeds. Can Treecko learn to master this move, and who do the watermelons belong too?
Having earned the Dynamo Badge, Ash is going to the next Gym, but wonders where it is. May knows what their next destination is - Fallarbor Town where May's going to another Pokémon Contest. However, Max tells that the next Gym is in Lavaridge Town, so a dispute between Ash and May is here - which Town to go first? Brock calms them down and Max tells them that the Fallarbor Town is near Lavaridge Town, so they can visit both cities.
Team Rocket is looking for the gang, but they get hungry. Team Rocket spots a field full of watermelons. As they begin to grab them, they see an enormous watermelon which begins to roll. However, the watermelon is actually an Electrode painted like a watermelon. The Electrode blasts them off, so the three watermelons begin to fall down in a river. The gang is having lunch time while Max spots something in the river. It are the watermelons - Ash orders Pikachu to use Iron Tail, but May gives them to Brock who slices them.
Ash spits the seeds, apologizing to May for manners. Ash thinks of Treecko - he gives the watermelon so that Treecjko can practice Bullet Seed move. Ash tells to May that he recalls Shiftry using such attack before. Ash demonstrates to Treecko how it is done, so Treecko tries it. Ash and Treecko practice more, with Treecko's attack being much more powerful. However, they are attacked by a Grovyle. Slugma appears as well. Grovyle uses Bullet Seed and Slugma Flamethrower. A girl appears, accusing the gang being the thieves.
The girl is pretty upset, since those were her watermelons. Natasha, the girl, denies everything, so the Electrode goes to her. Natasha is confident they are the thieves, but Electrode denies. Natasha blames herself, but Ash calms her down. Natasha introduces herself and the gang does so too to her. The gang visits the field and Brock is amazed that everything is hers, but it takes a lot of responsibility. Natasha points to her Pokémon who also protect the fields.
Natasha says that she's good in double battle, with Ash responding he's made it to Top eight in the Johto League, so Natasha challenges Ash to a double battle. Natasha sends Slugma and Grovyle, while Ash sends Treecko and Corphish. Treecko uses Pound against Grovyle, while Corphish uses Bubble Beam against Slugma. Grovyle dodges and uses Bullet Seed to negate Bubble Beam. Grovyle uses Bullet Seed on Treecko, while Slugma uses Ember on Corphish. Corphish uses Harden and Treecko hides behind Corphish. Treecko uses Quick Attack on Grovyle, while Corphish uses Crabhammer on Slugma.
Grovyle dodges and uses Leaf Blade on Corphish. Grovyle uses Bullet Seed and Slugma uses Flamethrower. Corphish uses Harden, with Treecko hiding behind Corphish. Corphish is tired, but can still continue to fight. Team Rocket appears again, thinking of whether they should steal the watermelons. Meowth imagines that if their boss was in a desert to set a new base up for Team Rocket, he'd been given the watermelons.
Treecko uses Pound and Corphish uses Bubble Beam. Grovyle evades and uses Leaf Blade on Corphish. Slugma uses Body Slam and Grovyle Bullet Seed, while Treecko goes behind Corphish and Corphish uses Harden. However, Slugma goes onto Corphish and Grovyle uses Bullet Seed on Treecko. Treecko grbas onto Corphish's right claw, while Corphish uses the claw as Crabhammer on Slugma. Treecko is launched and uses Quick Attack on Grovyle and Slugma. Grovyle uses Solar Beam, while Corphish uses Harden and Treecko goes behind Corphish. Slugma uses Flamthrower, while Corphish uses BubbleBeam. Both attacks damage one another, so both Pokémon are defeated.
As they are about to continue the fight, Electrode warns Natasha of watermelon thieves. Team Rocket collects the watermelons inside a mechanical Cacnea. The robot gets all the watermelons and attacks using the seeds. Grovyle uses Bullet Seed, with Treecko watching the attack. Meowth uses a launcher to stop Grovyle from usig Bullet Seed. Treecko uses Bullet Seed, but fails. Treecko tries the second time, succeeding to destroy the basket where watermelons are. Pikachu uses Thunderbolt, blasting them off.
Ash and Natasha continue their fight - Treecko uses Bullet Seed, but fails again. Grovyle uses Leaf Blade, but Treecko dodges the attack and uses Pound. Grovyle uses Bullet Seed, but Treecko dodges using Quick Attack. Both Pokémon are beginning to be tired, so Grovyle and Treecko use Bullet Seed, but Treecko has less power, so Natasha's Grovyle wins. Everybody eats watermelons, complimenting Natasha for such taste. Ash spots Treecko, so both Pikachu and him try to cheer him up. When it fails, they spit seeds on Treecko, so Treecko gets angry and uses Bullet Seed on them. Brock, May and Max praise Treecko for mastering the attack, though Ash does not think so, as he and Pikachu got hurt.
- Featured Pokémon: Poliwrath, Taillow, Combusken, Mudkip
- From this episode, the "Who's that Pokémon?" is replaced by a Pokémon trivia quiz.
- This was Ash's second double battle. The first one was against Forrester in AG014: All in a Day's Wurmple.
- When Ash orders Treecko to attack, he calls it Harden instead of Pound.
- When Slugma attacked the gang, it was Flamethrower, although later, when Max praises Slugma's attack to Natasha and when Natasha orders the attack, they say it was Ember.