Set in Rome during AD 72, the novel stars Marcus Didius Falco, an informer and imperial agent.

Falco's closest friend, Petronius Longus, has finally caught one of the leading criminals in Rome, Balbinus Pius.

But a quirk in Roman law allows a convicted felon, even a murderer, time to depart before the sentence is carried out.

Balbinus' departure has left a vacuum in the underworld of Rome, and there is a crowd of criminals trying desperately to fill the void.

A couple of murders, a kidnapping or two, and more suspects than Falco cares to count takes him, and his patrician girlfriend Helena Justina, to places a family shouldn't have to go.