Following the events of the Master Tournament, Ash, Goh, and Chloe travel to the Paldea region, invited by the renowned Orange/Grape Academy Principal Clavell to investigate anomalies in the mysterious Area Zero, a place that defies the natural laws of the Pokémon world. There, ancient forces stir, and the Legendary Pokémon Koraidon and Miraidon may hold the key to preventing a catastrophe that threatens time and space.

After the events of Mega Voltage, Liko, Roy, Dot, and Ult discover that Mega Evolutions are just the beginning. A new, ancient force called Nexus begins to awaken in the Pokémon world. Lost artifacts known as Fragments of the Eternal appear in different regions, and each one holds the secret to a new, unknown form of evolution... called NEXUS EVOLUTION. This new evolution transcends Mega, Z, Dynamax, and Terastal. But activating it requires more than strength: it requires a deep emotional connection and a shared history with the Pokémon. Meanwhile, a shadowy new organization called the Void Clan attempts to gather the Fragments to resurrect an Ancient Pokémon that was erased from history because it was too strong to exist.