In Roman times, the Seven Ancient Wonders of the World held a deep fascination. Two of them were in Egypt: the Great Pyramid of Giza and the Lighthouse at Alexandria. Marcus Didius Falco's wife, Helena Justina, is determined to see them before her next confinement. Conveniently, Marcus has an uncle with a house in Alexandria. For this innocent reason (he says) they sail to Egypt. As soon as they arrive in Alexandria, a suspicious death occurs at the famous Great Library. The authorities rapidly hand Falco the investigation; he is, after all, the well-known informer from Rome and the Emperor Vespasian's fixer. He was one of the last to see the victim alive and, should the investigation fail, it is he who'll get the blame ...