It's 76 A.D. during the reign of Vespasian and the Roman holiday of Saturnalia has begun. The days are short; the nights are for wild parties. But not for Marcus Didius Falco. Falco is an informer by trade - his job is to uncover unwelcome truths and deal with sensitive situations, frequently at the behest of the imperial government. And just such a case has arisen. A general has captured a famous enemy of Rome, and brings her home to adorn his eventual Triumph as a ritual sacrifice. But everything goes wrong from there - first she acquires a mysterious illness, then a young man is horrendously murdered and she escapes from house arrest.
     Marcus Didius Falco, hired to find her and return her to custody before Saturnalia is over, is pitted against his old rival, the Chief Spy Anacrites. The two of them are in a race against time to find the fugitive before the public learns of the situation, making the government look stupid. Falco, however, has other priorities. Helena’s brother Justinus has also vanished, perhaps fatally involved once more with the great lost love of his youth.
     Against the riotous backdrop of the season of misrule, the search seems impossible and only Falco seems to notice that some dark agency is bringing death to the city streets…