After crash landing on Valencia Island, Ash, Misty, and Brock set out to find Professor Ivy's lab. Once there, Professor Ivy shows the gang the mysterious Poke Ball (Named the "GS Ball" due to it's Gold and Silver colors, and the letters 'GS' carved into it).
Meanwhile, Brock has a revelation about Professor Ivy and her scientists, and decides to stay on the island.
A young boy named Ash Ketchum embarks on a journey to become a "Pokemon Master" with his first Pokemon, Pikachu. Joining him on his travels are Brock, a girl-obsessed Rock Pokemon Trainer, and Misty, a tomboyish Water Pokemon Trainer who may have a crush on him. Ash and Co. end up traveling through various regions, including Kanto, the Orange Islands, and Johto, and then enter the Pokemon League competitions there.
Along the way, they run into many confrontations with Jessie, James, and Meowth, a trio of Pokemon thieves who are apart of an evil organization called "Team Rocket". But every time Team Rocket try to do their evil deeds, they fail thanks to Ash and his Pokemon.