In France, river navigation is booming. Today, it is the least polluting and most environmentally friendly means of transport. It has become a real alternative to road transport. More and more young people are attracted to this very particular way of life.

Allison, Valentin, Jérémy and Clément are all four young sailor apprentice. One week per month, they take courses at the CFA of Inland Navigation. The rest of the time, they sail on the Seine, 24 hours a day, aboard a cargo or passenger transport ship. Under the responsibility of their apprenticeship master, they learn the trade hoping to one day become the owner of their boat. Along the water, this film takes us to discover their universe.