Also published: London : Headline, 2011. 497 p

The city of Rome in AD 51 is a dangerous place, even for Emperor Claudius. Treachery lurks on every corner, and a shadowy Republican movement, 'the Liberators", has spread its tentacles wide. It is feared that the heart of the latest plot lies in the ranks of the Praetorian Guard, who have free access to the Emperor, and are known to be easily corruptible. Uncertain of whom he can trust, the Imperial Secretary Narcissus summons to Rome two courageous men guaranteed to be loyal to the grave: army veterans Prefect Cato and Centurion Macro