When Ash, Misty, and Brock run to investigate a mysterious chorus of bells that spontaneously ring out, they chance to meet their old friend Morty and a Pokémon researcher of his acquaintance, Eusine. Morty and Eusien discover that the sacred Crystal bells, which are said to ring when a legendary Ho-oh returns, are missing. Since the bells were also used to heal the Bug Pokémon living in that area, these pokémon lash out against their human neighbors, covering the town with their webs. Ash and friends decide to get to the heart of things and in the forest find Team Rocket restrained by webs and hanging from a tree. Ash, Misty, Brock, Morty, and Eusine begin to battle with the Bug Pokémon. Can they restore the harmony to these once peaceful pokémon?