Ash, Brock, Misty and Pikachu are lost deep in the mountains. As they press forward on a rough road not even shown on their map, they suddenly hear a large explosion. Running toward the sound in surprise, the party emerges on a construction site where tractors are building a tremendous dam. Ash learns that the foreman is trying to recruit skilled Pokemon trainers because ground Pokemon, Diglett, are interfering with construction and delaying the completion of his work. The foreman has been recruiting Pokemon trainers to get rid of the Diglett. He will award free passes for travel to a luxurious natural hot springs to anyone who can accomplish this. As Ash scopes out the recruits, he notices a familiar enemy in the mix, Gary.