Summer, 1946. The Cousteau family - Jacques (Lambert Wilson), his wife Simone (Audrey Tautou) and their two sons - live in their beautiful beach house: a paradise, but it’s not enough for Jacques. Marine officer, oceanographer, explorer, director - all his life Jacques Cousteau will respond to the beckoning of the sea, becoming an international celebrity. At the cost of endangering his relationship with his son Philippe, which will always be stormy and conflicted. The film follows this prevalent tension in order to narrate, through triumphs and shipwrecks, the experience of a complex man, the great adventure of a father and son on board the Calypso and the allure of the ocean, its depths and its mysteries. An allure that is worth living and dying for.