A girl and an orca become inseparable on a research ship hunting for a creature that may not exist anymore. The show never stops moving, there's always a new current to follow, another mystery in the water, another reason to dive deeper. It builds something rare in children's anime: a world where grief doesn't paralyze you, it redirects you toward something worth protecting.
Nanami arrives aboard her father's research vessel carrying grief and displacement. Her mother is gone, and the ocean is now her home. Scott Simpson hunts the legendary Glowing Whale with scientific precision, but when he discovers only skeletal remains, his mission transforms into something gentler: protecting the creatures rather than studying them. The girl finds companionship in an orca she names Tico, a daily ritual of swimming that becomes her anchor to this floating world. Somehow, impossibly, she begins to breathe underwater. Her father watches in disbelief as she acclimates to a life between two worlds. When danger pulls Nanami beneath the waves, a magnificent creature emerges from the depths to save her. The Glowing Whale surfaces at last, not as scientific prize but as guardian. What begins as a story about loss transforms into something quieter and more profound: a young girl discovering that healing comes through connection. With her father, with Tico, and with the vast ocean itself. Adventure and domesticity interweave across seven seas.