Six years after the battle for Rome, the truce between the two emperors has failed and Aurelius Castus is again in the frontline. Six years after the battle for Rome, the truce between the two emperors has failed and Aurelius Castus is again on the front line.
When a treacherous act of murder throws the western provinces into turmoil, Castus is ordered to take command of the military forces on the Rhine. But he soon discovers that the frontier is a place of peril, where the boundaries between civilisation and barbarism, freedom and slavery, honour and treason become blurred.
With all that he loves in danger, Castus and a handful of loyal men must fight to defend the empire. But in the heat of battle, can he distinguish friend from enemy?