Nanami Simpson is a young girl. Her mother dies when she is young, and she goes to live with her father, Scott Simpson, on board a marine research vessel, the Peperonchino. Her father is a marine biologist, and he is in search of a creature known as the glowing whale. When he finds the bones of one of these, he is saddened, and resolves to change his mission toward preserving and caring for the creatures. Nanami befriends an Orca which she names Tico, and she goes swimming with it every day...