In first century A.D. Rome, during the reign of Vespasian, Marcus Didius Falco works as a private "informer," ferreting out hidden truths and bringing villains to ground. But even informers take vacations with their wives, so Falco and his wife, Helena Justina, with their two young children and others in tow, travel to Alexandria, Egypt. But they aren't there long before Falco finds himself in the midst of nefarious doings — when the Head Librarian of the world-famous library is found dead under suspicious circumstances, in his office with the door locked from inside.

Falco quickly finds himself on the trail for dodgy doings, malfeasance, deadly professional rivalries, more bodies, and the lowest of the low - book thieves! As the bodies continue to pile up, it's up to Falco to untangle this horrible mess before the killer begins to strike closer to home.