As our heroes and their Pokémon enjoy another fine meal prepared by Brock, Golbat begins to act strangely and flies away. Brock, Ash and Misty chase after the Flying-type and end up at an archaeological dig. When they meet the intelligent and beautiful archeologist, Tierra she explains her ultra-sonic equipment had just been destroyed and perhaps its errant waves attracted Golbat. She also tells our heroes of an ancient golden mask and scepter, once belonging to a queen who had the power to control all Pokémon. She is now looking for a buried temple said to contain these two priceless artifacts and asks Brock if his Golbat will use it's Sonic attack to help her locate the exact placement of the temple. Overhearing our heroes, Team Rocket employs their latest mechanical menace, the Dig-a-Tron to beat the gang to the temple. When Jessie dons the mask and scepter she has the power to control all Pokémon, even Pikachu! What will become of the Pokémon under Jesse's rule?
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.