Summer, 1946. The Cousteau family - Jacques, his wife Simone and their two children Philippe and Jean-Michel - live in their beautiful house by the Mediterranean sea. By day they dive, by night they watch the stars. It's paradise on earth.
But Jacques is never content. He lives and breathes adventure and believes absolutely in the virtues of progress. With his invention, the aqualung, his recently acquired vessel the Calypso, and a crew of free-spirited adventurers he is ready to cross the world's oceans.
Ten years later, back from the boarding school to which he was sent with Jean-Michel, Philippe finds his father greatly altered – an international celebrity with megalomaniac dreams of grafting gills to humans and creating underwater cities.
Jacques cannot see it yet, but Philippe already understands that progress and pollution have begun to lay waste to the submarine world. Despite their mutual love and admiration, violent conflict between these two passionate men is inevitable. But on their greatest adventure together aboard the Calypso, in Antarctica, they will find each other - before tragedy strikes.