A crystal catastrophe is unleased upon Greenfield, and Ash, Pikachu, and friends must figure out how to undo the damage to the once-beautiful town. But the unthinkable happens when Ash's mother is kidnapped by the powerful Entei, a Pokémon thought to have existed only in legend. Now Ash must go to her rescue, uncertain of what he'll uncover when he unlocks the real secret power behind the unbelievable turn of events: a young girl whose dream world is being turned into a nightmarish reality by the mysterious and unstoppable Unown!