It is a sunny day when Armin calls his brother Wolf to show him a miracle: the construction of the "road that never stops." A project that leaves them ecstatic, the technical marvel of the Roman enemies, capable of creating from nothing a road that crosses forests, rivers, swamps, and does not deviate from its course even in front of mountains.

Suddenly, the two boys come face to face with a Roman patrol. The soldiers capture them, but their fate is neither death nor slavery. Because the two of them are sons of a king. Sigmer, their father, is a proud and formidable warrior, a German prince whom his tribe respects and loves. His only weakness was his secret friendship with Drusus, the great enemy, the Roman general who was lost prematurely, and whom Sigmer had secretly known and admired.

The two young men are forced to leave their land and their father and are taken to Rome. They are barbarians but also princes. They will be trained according to the customs of the Empire until they become officers of the German auxiliaries in Augustus' legions. Under the watchful eye of the rigid centurion Taurus, they will learn a new language, adopt new habits, and a new way of thinking.

And how can Armin and Wolf, raised in the forests, not be enchanted by the wonders of Rome? The two boys will become Arminius and Flavus, Roman citizens. But has the voice of blood truly been silenced within them? Can their faith in their ancestors lead them to the decision to betray the land that adopted them?