As a result of human greed, the land where people lived sank and sea levels rose. Humans had to adapt to a world dominated by the oceans; many chose to build giant ships and explore the vast seas, while quite a few dived into the ocean and formed bonds with sea creatures. The same is true for a young girl named Nala. Her life changes when she meets a lonely creature—a giant orange fish called “Nepo.” Meanwhile, her older brother, Moris, tries to explore the ocean’s surface and encounters mysterious creatures he has never seen before. This encounter takes them to a world far vaster than they could have ever imagined. The secrets of the ocean, rising sea levels, conflicts between two worlds, and how to survive in this new world.