At the beginning of the Second World War Salvatore Todaro is in command of the submarine Cappellini of the Italian Royal Navy. In October of the year 1940, while navigating in the Atlantic, the outline of a merchant ship comes into view, sailing without lights through the darkness of the night. She is the Kabalo, which later turns out to be a Belgian vessel, and suddenly opens fire on the submarine and its Italian crew.
A brief but fierce battle ensues in which Todaro sinks the enemy ship with gunfire. And it is at this point that the commander takes a decision that will go down in history: to rescue the twenty-six members of the Belgian crew from drowning in the middle of the ocean and tow their lifeboat to the nearest safe port, as required by the law of the sea. To do so he was obliged to remain on the surface for three days, exposing the submarine to enemy forces and putting at risk his own life and that of his men.
When the captain of the Kabalo, put ashore on the island of Santa Maria in the Azores, asked him why he had been willing to take such a risk, disregarding the instructions of his own superiors, Salvatore Todaro responded with the words that have made him a legend: “The others do not have, like me, two thousand years of civilisation behind them.”

DIRECTOR'S NOTES:
The man at the helm of a Roman trireme two thousand years ago is the same as the one commanding a submarine in the Atlantic in 1940, at the height of the war. That man’s name is Salvatore and he is strong. He sinks enemy ships without fear and without pity. But the helpless enemy is no longer an enemy. He is just another man and so he saves him. Because the truly strong human being is the one capable of offering a helping hand to the weak. Salvatore knows the eternal laws that govern the sky and the sea and he knows that they are superior to any other law. Whoever saves one man, saves mankind.