The Pokémon League tournament is beginning in the Indigo Plateau. In the audience, the President of the PokéFan Club is excited to see a Spearow, but a mysterious trainer takes it away, intimidating the President. The trainer registers for the tournament, amused to see that Red, Blue, and Green are entering as well.
Red and Blue win their separate matches and agree to face each other in the finals; after all, all previous Champions have been from Pallet Town. Red sees Green trying to scam a trainer and confronts her, but she confounds him when she reveals she is in the semifinals—and she, too, is from Pallet Town.Red finds out that he will be battling Blue in the semifinals, not the finals, while Green is battling the strange "Dr. O" in her semifinal match. Green sends out her Jigglypuff while Dr. O sends out his Spearow. The crowd is surprised and dubious at Green's cutesy choice, but Red supposes she's trying to get Dr. O's guard down. Green wonders how Dr. O could have gotten to the semifinals with his Spearow.
Green's Jigglypuff unleashes a devastating attack which had won all of Green's previous matches on the first move, but Spearow survives it, dive-bombing Jigglypuff with Fury Attack. Jigglypuff uses Sing, but Spearow fends it off.
Red shouts for Green to swap Jigglypuff for a flying-type Pokémon, but Green responds that she doesn't own any. Red guesses that her opponent knows this.
Dr. O suddenly appears behind Green, telling her that, no matter the reasons, stealing will never help her win. Green jumps away and has Jigglypuff use Disable on him, and upon returning Jigglypuff, unleashes Blastoise for an aerial attack: his cannons blast out water, propelling him into the air. He smashes Spearow and Dr. O with Hydro Pump, but Spearow uses Mirror Move, hitting him back. Blastoise collapses to the ground, and Spearow swoops in the air before him, making Green cry out and flinch away.
Dr. O, whose facial bandages have fallen away due to Hydro Pump, explains that six years ago a little girl was kidnapped by a bird Pokémon. As his grandson had been the same age, five, "Dr. O" had decided to get involved in the search, thus memorizing the girl's face…which he later saw on a photograph of a girl stealing a Squirtle from his lab.
He completely removes the bandages from his face, confirming that he is Professor Oak.
Green snarls and her Blastoise manages a final attack, which Spearow turns back on him with Mirror Move. Blastoise faints.
Professor Oak asks Green why she stole his Squirtle. Green confesses that as she was growing up, she had no family or anything; all she knew was that she is from Pallet Town, Kanto. When she'd heard about two great trainers who'd left Pallet with pokédexes to journey, she'd wanted to receive a Pokémon and pokédex from Oak to join them.
Oak gives Green his third pokédex, acknowledging her as a trainer of Pallet Town. After that, Oak withdraws from the competition, transforming the semifinal match between Red and Blue into the finals.