Ash and Pikachu cross paths with Jackie, a Pokémon Ranger escorting a Manaphy egg, and the meeting draws them toward a temple said to hold the Sea Crown, a treasure sealed away by an ancient civilization known as the People of the Water. A pirate calling himself the Phantom wants both the egg and the crown for himself, and Ash joins Jackie's mission to keep them out of his hands. This manga adapts the ninth Pokémon film across four chapters.