The year is 54. "on a strip of sand in Gaul, a grubby urchin watches a ship land, and a man with a badly scarred face disembark. The man is Pantera, assassin and spy for the Legions, returning from five years' undercover in Britannia. Pantera is sick of spying. But a deadly combination of old loyalties and a sense of unfinished business combine to lure him homeward to the city of Rome. Charged by his former mentor and spymaster, the Machiavellian Seneca the Younger, to root out the revolutionaries responsible for the city's seething unrest, Pantera soon finds that the main trouble maker is none other than his closest friend Saulos, a recent convert to the new religion of Christianity, and who is planning the biggest single act of terrorism the Roman empire has known."