In a scuffle with Team Rocket, Ash and friends are thrown from the ship bearing them to the Whirl Islands. As powerful whirlpools draw them toward impending doom, a mysterious form under the sea shifts the powerful undertow, drawing them to safety. Shortly thereafter, a Corsola comes skipping over the sea's surface and guides the children back to a ship wherein awaits their old friend, Professor Elm. They ride the ship to a bustling harbor in the first of the Whirl Islands. There they learn of an upcoming competition in which Water Pokémon trainers will vie for the title of Whirl Island champion. (thetvdb.com)