Legend speaks of a hidden Sea Temple created by the People of the Water, which holds a powerful treasure known as the Sea Crown. Ash and Pikachu meet Lizabeth, a descendant of the People of the Water, and Jackie, a Pokémon Ranger on a secret mission to protect a Manaphy Egg and find the Sea Temple. The Phantom, a nefarious pirate, plans to obtain the Sea Crown and take over the world, but he first needs the Manaphy Egg! Now Lizabeth and Ash must help Jackie protect the Egg and stop the pirate!