The film focuses on Celebi who travels to the future with a boy named Sam when being chased by a hunter. Ash, Misty, Brock, and Pikachu are on their way to the next gym in their Johto journey and get a lift from a man named Maki who takes them to his hometown of Arborville. They see a Suicune (who was actually the first Pokémon Ash saw in Johto). When they plan to enter a forest that is claimed to have many unusual and rare Pokémon, they are warned by an elderly lady about the "Voice of the Forest" which may carry a person off to a different period in time unless those hearing it stand still.