I century BC. Defeated by a ruthless enemy on the edge of the known world, the surviving legionnaires are captured by the Parthians. Abandoned by Rome to their fate, these people are the Forgotten Legion. Among them are three friends: the Gaul Brennus, the Etruscan soothsayer Tarquinius and Romulus, a runaway slave and the illegitimate son of a Roman patrician. United by hatred of Rome and the dream of Freedom, they confront the savage tribes that surround them, as well as much more insidious enemies in the ranks of the legion itself... Meanwhile, Fabiola, the twin sister of Romulus, keeping the hope that her brother is alive, is forced to fight in the name of own salvation. Freed by a powerful lover but surrounded by enemies on all sides, she travels to Gaul, where her patron faces off against fierce local warriors. But more than her heartfelt affection, she is driven by a thirst for revenge: only he, Caesar’s right hand, is able to help her carry out her insidious plan...