On their way to Blackthorn City, Ash, Misty, Brock, and Pikachu run into a female Trainer with a Smoochum. Evidently, Brock fell in love with her, but he was not given much of a chance to display his affection, as the Trainer was eager to start the battle. Using her Smoochum, Josephine, against Ash's Pikachu, she begins the battle with a Sweet Kiss attack. Pikachu dodges it by jumping over Smoochum, landing on the other side. Smoochum turns around and proceeds with the many Sweet Kisses, not one of them hitting Pikachu, who stood still, waiting for Smoochum to come closer. Just as Smoochum was approaching, Pikachu uses Agility and Smoochum hit the ground, after which Pikachu hit it with a Quick Attack from behind.
Just as Pikachu is about to use a Thunderbolt, the Trainer cancels the battle, claiming that they've had enough, and that such an intense battle tired her out. Ash, who was just warming up, begs her for another battle, but the Trainer was too exhausted. Instead, she recommends they'd go to the Battle Park, which she describes as a great place where a lot of Trainers bring their Pokémon in order to battle, and is run by professional Trainers, and the Pokémon who battle there have been well taught to follow their Trainer's commands, and she also said that the Battle Park has almost every Pokémon that exists, so Ash, Misty, Brock, and Pikachu decide to go there.
Meanwhile, Jessie, James, and Meowth are busy cleaning Poké Balls at said Battle Park, where they apparently are employees. When they were finally done with the last one, their supervisor enters the enclosed room in which they're sitting and tells them that since the park is closed, it'd be a good time for them to clean it up, but first, he hands them another box of Poké Balls. He laughs as they scream, and explains that he had the hard work; having to go shopping. Jessie, who was now furious, slams her fists on the table. Meowth suggests that they'd take the Poké Balls and leave, but James said that they hadn't even gotten their first pay-check yet, whereas Jessie was certain it would not be much anyway.
They turn around as they heard Ash's voice coming from outside, but him, Misty, and Brock shortly assumes that the Battle Park was closed, as there were no workers or Trainers around. Just as they were about to leave, Jessie approaches and welcomes them to the park, and guides them to the reception, in which James was standing. He offers them the opportunity to challenge the strongest Pokémon in the park, whose Poké Balls were being held in a basket, which Ash promptly accepted. Jessie brought them to a large gate, and told them to enter and that she'd be back soon. Despite wondering where the other Trainers were, they kept on going until they heard Jessie's voice, only this time, she and the rest of the trio were impersonating other Trainers. Ash hesitated, as he was uncertain of who would judge the battle, and none of the Team Rocket members want to, so Brock decides that he would judge it.
The battle started, and James took a Poké Ball from the basket, which turns out to be a Venusaur. Ash chose his Cyndaquil, as Venusaur is a Grass-type Pokémon, and Cyndaquil is a Fire type. James starts off with a Razor Leaf attack, saying he was used to Grass-type moves from having a Victreebel. Cyndaquil dodges all the leaves, which instead hit three trees, causing all of them to fall. James continues with a Tackle attack, which Cyndaquil attempts to dodge, but was hit and thrown into a tree. James now uses a Vine Whip attack, which Cyndaquil manages to dodge by jumping away, causing the vines to instead hit another tree which also fell. James now uses another Vine Whip attack, this time hitting Cyndaquil who had tries to dodge it, but instead crashes to the ground. Another powerful Razor Leaf attack was fired at Cyndaquil, who uses Smokescreen. When the smoke had faded, James and Venusaur could not find Cyndaquil, who had jumped up above Venusaur and now uses a Swift attack, and follows it up with a Flamethrower. Venusaur got up and uses a Solar Beam attack, which overpowers the Flamethrower that Cyndaquil had used as a counter. It hit Cyndaquil with enormous strength, and this turns out to be the end for Cyndaquil.
The second battle has now begun; while James and Meowth were arguing about who were to go next, Jessie sneaks in behind them and grabs a Poké Ball containing a Charizard, and Ash responds by choosing his Totodile. Jessie, used to fighting with her Arbok, uses a Poison Sting attack. As nothing happened, Ash uses a Water Gun attack. After Jessie rejects a guide book from Meowth, she orders the Charizard to use a Dig attack, which, to everybody's surprise, it did. Jessie now commands an Iron Tail attack which hit Totodile, but who got up again. Charizard uses another Iron Tail attack, but Totodile dodges it and uses a Headbutt attack, after which it uses a Scary Face attack, but Charizard uses an even scarier face, and they continues using Scary Face until both their Pokémon collapsed. Totodile got up however, and uses another Water Gun. After some thinking, Jessie commands the Charizard to fly up and dodge it, and use a Flamethrower attack. Ash responds to this by using yet another Water Gun, which was overpowers by the Flamethrower, but Totodile got up once again. Jessie uses another Flamethrower, but Totodile aims a Water Gun attack towards the ground, causing it to fly up behind Charizard, and uses another Water Gun on Charizard, who crashes to the ground, which was the end of the match.
As the third battle was about to start, James and Meowth once again argues about who were to go next, and once again, Jessie took this spot, and the remaining Poké Ball had contains a Blastoise, so Ash chose his Pikachu. Jessie chose to battle by the book this time. While she was reading, Pikachu uses a Quick Attack. Jessie got her act together and orders Blastoise to use a Skull Bash attack, which Pikachu manages to dodge. Jessie read up on how to counter speed, and commands Blastoise to use a Bubble attack. Nonetheless, Pikachu got past all of them and uses another Quick Attack. Ash decides to end this battle and Pikachu uses a Thunderbolt, but Blastoise withdrew, after which it uses a Hydro Pump attack. Pikachu was hit and thrown in to a tree, and Blastoise uses another Hydro Pump, keeping Pikachu stuck to the tree. Ash now told Pikachu to use the most powerful Thunderbolt possible, and although it got Pikachu down from the tree, Blastoise was still standing up. Pikachu now uses a Thunder so strong it causes the ground to split, and Jessie, wanting to stop it, got in the way and was also hit. An enraged Jessie calls out her own Arbok.
Meanwhile, James and Meowth had grabbed the balloon and grabs Pikachu as well. Jessie swiftly removes her disguise, revealing her true Team Rocket identity. James also reveals they had taken a sack of park Poké Balls as well. Out of nowhere, a park guard shows up, informing them that they cannot take those. As Team Rocket was about to escape, Ash chose Totodile, and Misty chose her Politoed. Ash and Misty both commands their Pokémon to use a Water Gun attack, but only Totodile actually uses one, which regardless broke the steel arm holding Pikachu. Misty, upset with her Politoed, told it to use another Water Gun, which cut a hole in Team Rocket's balloon. As Ash, Misty, Brock, and the park guard approach Team Rocket's crashed balloon, Jessie, James, and Meowth call out the Venusaur, Charizard, and Blastoise. As Team Rocket basks in their power, the three Pokémon turn against them. The park guard proclaims that they are only obedient within the park. A combined Flamethrower, Hydro Pump, and Solar Beam hit Team Rocket, all three at once, causing them to "blast off again". As Ash, Misty, Brock, and Pikachu were continuing their journey towards Blackthorn City, they discuss the recent battle, and although it had "just been Team Rocket", Ash still had battled three very powerful Pokémon, and it had motivates him on his task to win his final Badge.