Children of the Sea

On the first day of summer break, junior high student Ruka is shut out of her handball club after a clash with a teammate and goes to the aquarium where her father works, where she meets Umi and Sora, two boys said to have been raised by dugongs. At the same time, fish begin vanishing from oceans and aquariums around the world, and strange lights are seen at sea. Drawn to the two boys, Ruka is pulled into a festival that the creatures of the sea are gathering for.