Rome: September, 96 AD. When the body of Sextus Verpa, informer and libertine, is found stabbed to death in his bedroom, there is no way in or out. The method and motive remains a mystery, so suspicion falls on his slaves.
Pliny, a young senator, is ordered by Emperor Domitian to investigate. But the Roman Games have begun and for the next fifteen days the law courts are in recess. If Pliny can't identify the murderer in that time, Verpa's entire slave household will be burned alive in the arena.
Along with the poet Martial, Pliny’s investigation unravels a plot involving Egyptian cultists and a missing horoscope that will lead him through the tenements and brothels of Rome’s most decadent age, and finally to the palace itself, where no one is safe from the paranoid Emperor.
As the deadline approaches, Pliny struggles with the painful dilemma of a good man forced to serve a brutal regime—a regime implicated in conspiracy that touches the heart of Imperial Rome.