In the land of Hoenn, a girl named May travels to Prof. Birch's lab. She is attacked by a wild ghost Pokémon called Duskull. Scared, but unharmed, she travels on her bike to the lab in Littleroot Town.
Ash also travels to Littleroot Town and is going to sign up for the Hoenn League. Team Rocket's failed attempt to catch Pikachu has left the little yellow Pokémon dangerously ill, so Ash goes to seek help. Jessie is feeling somewhat depressed, as she does not have any motive to hunt Ash's Pikachu. Ash arrives in town to discover that Littleroot does not have a Pokémon Center! Ash rushes to the nearest telephone booth and talks to one of the assistants. The assistant alerts Prof. Birch. Professor Birch thinks that Pikachu can be cured. However, Pikachu has disappeared, so they see they need to find it, quickly. Delirious with fever, Pikachu has run off into the forest.
Meanwhile, May arrives at the lab in order to receive her first Pokémon to find that the Professor is not there. The assistant tells her that he drove into the woods, so she rides the bike after him. In the woods, while Professor Birch was searching for Pikachu, he tumbles down a cliff and lands on a Poochyena. He is suddenly surrounded by a group of the Pokémon and he looks like he is in trouble. Suddenly, May arrives and the Prof. tells her to take one of the Pokémon out of his bag and use it to battle the Poochyena. She ends up throwing Mudkip. Birch tells Mudkip to do a Water gun attack. However, Mudkip attacks May instead of Poochyena, soaking her wet.
Ash finds Pikachu, but Pikachu thinks (because of the disease) that Ash is his enemy, so he attacks him. Pikachu flees and falls down the cliff, but Ash catches him while holding onto a tree in the cliff. Pikachu bites Ash, but Ash still climbs, as May and Prof. Birch arrived with the rope. Pikachu soon regains its memory (although still ill) and licks Ash's wound. As the group is about to leave, Team Rocket appear before them in a giant robot. They reintroduce themselves May and the Prof. know who they are. Jessie still does not care about this mission and James and Meowth do the dirty work as they launch an arm that grabs Pikachu and succeeds.
Struggling to get free, Pikachu lets loose a super-powered Thunderbolt. Since the robot was designed to absorb Pikachu's electricity, it has no effect. Nevertheless, Pikachu continues to unload high-powered Thunderbolts, using up all of his stored electricity. Unfortunately, one of the electrical surges destroys May's bike, as she gets very devastated by that act. The robot, however, was not designed to absorb this amount electricity, and so it overloads and explodes, sending Team Rocket blasting off for the first time in the Hoenn Region. Jessie, however, realizes that they are hunting Pikachu for their boss, Giovanni.
Back at the lab, Prof. Birch and his assistant perform some tests on Pikachu, to see if he is okay. May comes and asks Ash about Pikachu, then decides to pick her first Pokémon. Birch introduces her Torchic, Mudkip and Treecko. Since Mudkip was not very loyal and she finds Treecko somewhat unpleasant-looking, May picks the Fire Pokémon, Torchic, as she finds it cute. Prof. Birch gives her a Pokédex and she quietly says how she really doesn’t like Pokémon, but corrects herself in time before Ash and Birch heard this. The next morning, she goes to the room where Ash and Pikachu are sleeping. May's damaged bike due to Pikachu's Thunderbolt makes her angry, but she decides to ask Ash if she can go with him on his journey. He agrees and they head over to Oldale town as Ash's journey in Hoenn begins.
To denounce the evils of truth and love, to extend our reach to the stars above. Jessie. James. Team Rocket blasts off at the speed of light. Surrender now or prepare for an out of this world fight. Meowth, that's right!
Pikachu, where's all your Thunder Bolt?! Well I for one have been doing my homework now dig this! I've come up with a machine that'll beat that pesky Pikachu at its own nasty game. No matter how high these volts go this machine will absorb them!
"That's a water type." "Correct." "Yeah but that Mudkip wouldn't do a single thing that I asked it to do." "Really? How could that little guy cause trouble?" You're very fond of Pokémon aren't you Ash?
Ughhh walking all that way alone makes me nervous and my bike's destroyed thanks to your Pikachu, Mister. There must be a solution, a way to get to Oladale Town safely on foot. Heyyyyy why don't we go there together? I happen to know the way there. Really Ash I don't mind at all. It's no trouble! Shall we?
So with Pikachu fully recovered, Ash and May can begin their journey together. As they head for Oldale Town and the nearest Pokémon Center. Together they're sure to discover new Pokémon and new friends as well. One things for sure, even more adventures lie just ahead.