It is the fifth century of the Byzantium Empire. Flavius Belisaurius is son of the governor of Dorostorum City, and his father has two goals: to keep out the barbarians and to expose the deep roots of secular and ecclesiastical corruption. Seeking to prevent a raid, the governor enlists the help of the powerful magnate Senuthius Vicinus.

Vicinus's corruption is widespread but his support is crucial to win the battle. When Vicinus betrays this trust, Belisaurius Jnr witnesses the death of his father and the irretrievable tarnishing of his reputation. With Belisaurius's life changed for good, he swears vengeance on the man who betrayed his father and begins a journey from which there is no virtuous way back.