AD 51. Legionaries Cato and Macro have forged a bond that has survived war, rebellion and torture. Yet nothing has prepared them for a daunting mission on the deadliest battlefield of all: the bloody streets of Rome. Traitors are threatening to plunge the Empire into bloody chaos and no one can be trusted. The Emperor has ordered Cato and Macro to go on a deadly mission, working undercover to root out the traitors before Rome tears itself apart. As the true scale of the corruption dawns, they realise they are facing terrifying odds. Two men against many, in a desperate race to save not only the Empire, but each other...