In appointing a successor to his throne, the Emperor of Rome, Marcus Aurelius, chooses his adopted son Livius over his own son, Commodus. Prior to Livius' coronation, Commodus murders his father and proclaims himself the new emperor, prompting an epic reign of terror and corruption. His brutish tyranny alienates his brother, and the power struggle between Commodus and Livius culminates in the ultimate battle between the Barbarians and the Romans.