The series tells the story of Yann, a diving-mad teenager, and Marina, his adorable seven-year-old sister. Yann and Marina live with their uncle Patrick, an oceanographer, on Maotou, a remote paradise island in the Pacific Ocean. When Yann meets Zoom, a mysterious and remarkably intelligent white dolphin, an indestructible friendship begins. Always ready to help out those he loves and protect the weak, Zoom takes Yann on a series of exciting adventures, set in the fascinating, fragile and danger-filled underwater world, as well as on dry land.

Comedy and humor are central to the series, expressed through a host of colorful characters including Raoul, Marina’s pet koala; John-Sebastian, the chatterbox mynah bird; Loaf, the sloth; and other inhabitants of Maotou Island.