The Roman Empire is crumbling, and a shadow looms in the east…376 AD: the Eastern Roman Empire is alone against the tide of barbarians swelling on her borders. Emperor Valens juggles the paltry border defences to stave off invasion from the Goths north of the Danube. Meanwhile, in Constantinople, a pact between faith and politics spawns a lethal plot that will bring the dark and massive hordes from the east crashing down on these struggling borders.The fates conspire to see Numerius Vitellius Pavo, enslaved as a boy after the death of his legionary father, thrust into the limitanei, the border legions, just before they are sent to recapture the long-lost eastern Kingdom of Bosporus. He is cast into the jaws of this plot, so twisted that the survival of the entire Roman world hangs in the balance…

The Danubian frontier is weaker than ever, and a storm is gathering in the north . . . Deep winter, 376 AD: Emperor Valens has withdrawn the field armies from Moesia and Thracia to fight in the Persian War. The impoverished limitanei legions left behind to defend the banks of the River Danubius are now all that stand between the war-hungry Goths and heart of the Eastern Roman Empire. For Numerius Vitellius Pavo and the men of the XI Claudia, the brief from Emperor Valens is simple: to avoid war with the Goths at all costs while the Roman defences are so weak. But in the frozen lands north of the Danubius a dark legend, thought long dead, has risen again. The name is on the lips of every warrior in Gutthiuda; the one who will unite the tribes, the one whose armies will march upon the empire, the one who will bathe in Roman blood . . . The Viper!