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.