With Charizard gone and no fire Pokémon to call his own, Ash is overjoyed to come across a Cyndaquil in the wild. Before Ash captures the little Pokémon, though, he'll have to face another Trainer with similar designs.
Ash and his friends find themselves lost in a forest on their way to Azalea Town. As Brock looks for information in his guidebook, a Trainer called Koji approaches the group and demands to know if they have seen any wildCyndaquil around. Ash is immediately interested and begins searching through some nearby bushes for a Cyndaquil. Koji is irritated and storms off after Misty and Brock query his intentions. Ash runs off to continue his search, leaving his friends behind.
Meanwhile, Team Rocket sets their sights on Misty and Brock. Jessie and James complain about all of the menial jobs they had to take in order to raise money for a new machine. The trio then confronts Misty and Brock in their new Meowth robot and recites their motto. The trio soon notices Ash and Pikachu's absence and departs to find them. They soon spot Ash and Pikachu in the woods and attack them with their mecha. Pikachu uses Thunderbolt, but the mecha absorbs the attack and Team Rocket uses the energy to fire bubblegum bombs. Ash and Pikachu run and manage to dive into some shrubs for cover. However, the mecha soon finds the pair with its eye beam. James fires another bubblegum bomb, but it misses. Team Rocket pursues Ash, but the mecha trips over a tree root.
Ash and Pikachu soon emerge from the forest and come across a series a rock wall dotted with many small caves. When a Cyndaquil pops out of one of the caves, Ash scans it with his Pokédex and then starts to climb up to the cave. Koji arrives on the scene and spots Ash as he makes his ascent towards a Cyndaquil. He decides to intervene and has his Sandslash use Sand-Attack. The sand flies into Ash's face and causes him to slip back to the ground. Koji soon joins his Sandslash on a rock ledge and enter the cave system to pursue Cyndaquil. Cyndaquil also runs into the cave system. As Ash attempts to follow, Team Rocket shows up, but Ash says that he has no time for them and dashes into the cave. When Ash enters the cave, he sees several small holes that Cyndaquil could have gone into. Ash then sees Cyndaquil run passed him, but falls over as Sandslash dashes by.
Team Rocket fires a putty ball into the cave to lure Ash out. Meanwhile, Koji has cornered Cyndaquil, and his Sandslash tries to use Poison Sting on it. However, Ash grabs Cyndaquil while still running from the putty ball. Koji steps out to confront Ash, but is hit by the putty ball. As Ash rounds a turn, the putty ball hits the cavern wall and explodes. The force of the blast sends Ash, Pikachu and Cyndaquil flying out of the cave system. The trio are uninjured but Ash looks up and sees the Meowth mecha standing over him. Team Rocket sends out another bubblegum bomb and its stickiness pins Ash against a cliff wall. Ash lets Cyndaquil free and tells it to run before it gets hurt. Cyndaquil complies and as it begins to run up the rock wall, the Meowth mecha blocks its path with its fist. Cyndaquil is startled and remains motionless. As Team Rocket goes to use a Meowth punch, Cyndaquil's back erupts with fire and the small Pokemon soon engulfs Team Rocket's mecha in an overwhelming Flamethrower. The mecha begins sparking and crumbling from the intensity of the flames. Pikachu frees himself and Ash with Thunderbolt. Ash then throws a Poké Ball at Cyndaquil so it will not get hurt by the ensuing explosion, just as Team Rocket blasts off.
The dust settles, and Ash soon spots the Poké Ball lying nearby. He picks it up and throws it out, and much to his relief he has caught the Cyndaquil. Ash then commends Cyndaquil on its friendly nature and powerful Flamethrower attack. Misty and Brock arrive on the scene, and Ash explains that he went on to catch Cyndaquil. Koji emerges from the cave system and readies his Sandslash to attack. Ash holds him arms out and explains that he has already caught Cyndaquil. Koji challenges Ash to a battle over Cyndaquil. Ash accepts despite Brock's insistence that he doesn't have to, and even uses Cyndaquil in the battle, confident that it will use its powerful Flamethrower again. Koji declares that the match will be a one-on-one single Pokémon battle before the challenge ensues.
Koji makes the first move, and Sandslash attacks with a Fury Swipes. Cyndaquil wakes up in time to dodge the attack. Cyndaquil continues to evade Sandslash's attacks, impressing Ash with its technique. Sandslash is left exhausted and Ash commands Cyndaquil to use Flamethrower, but nothing happens. Koji demands his Pokemon continue battling and Sandslash continues to Slash away while Cyndaquil evades. Sandslash flicks sand into Cyandaquil’s eyes. It follows up with a Swift attack and lands a direct hit after Cyndaquil was unable to perform Flamethrower to counter. Ash decides to change his strategy and has Cyndaquil continue to dodge Sandslash's attacks. Soon enough, Sandslash knocks Cyndaquil into a tree. As Sandslash goes in for a finishing Fury Swipe, Cyndaquil leaps into the air and Sandslash's claw becomes stuck in the tree trunk. Cyndaquil dives down and lands a Tackle on Sandslash's head, ending the match. Koji recalls Sandslash and pulls out a net to snare himself Ash's Cyndaquil. However, the flames on Cyndaquil's back rise up and it finally lets out an impressive Flamethrower, scaring Koji away. Ash embraces Cyndaquil and declares that he has caught a new Pokémon. Elsewhere, Team Rocket looks up at the stars as they do another menial construction job.