Summer, 1946. Blues skies, blue seas. Jacques Cousteau leads his son Philippe into the warm waters of the Mediterranean.
Using a custom-made aqualung, for the first time in his life the boy breathes underwater and discovers the silent world his father was the first to explore – a magnificent, mythical realm thronging with multi-coloured life.
Ten years later, when Philippe is reunited with Jacques aboard the Calypso, he finds his father greatly altered. An international celebrity thanks to cinema and television, Jacques bestrides the world, leaping between non-stop flights, meetings, conferences and interviews. His projects grow ever more megalomaniac: he dreams of grafting gills to humans and creating underwater cities.
Racing forward relentlessly, Jacques is risking everything: his family first, but also the underwater world that he had discovered 20 years earlier, where pollution has already begun to lay waste.
Jacques cannot see it yet. Philippe will understand before him. Despite their mutual love and admiration, violent conflict between these two passionate men, from two different generations, is inevitable.
But on their greatest adventure together aboard the Calypso, in Antarctica, a still virgin continent at the world’s end, they will find each other, before tragedy strikes.