Bona is a lionfish who feels lonely. She has no neighbors, no friends, and wonders where she truly belongs. Determined to find her home and companions, Bona sets off on a heartfelt journey to find herself.
Herman follows the sound of the ocean to find his father in the central seas. He meets the ancient sea beast Leviathan, whose blood turns to gold and silver. Herman's hometown grows wealthy, but the ocean slowly suffers from pollution and human activity.