It’s A.D. 76 during the reign of Vespasian, and Marcus Didius Falco, a Roman “informer,” has achieved much in his life. He’s joined the equestrian rank, allowing him to marry Helena Justina, the Senator’s beloved daughter.

But now he’s just been hired to undergo a dangerous mission: to pry his brother-in-law Aulus, a scholar on the way to study in Athens, away from a murder investigation involving two dead women at the ancient site of the Olympic Games.

Traveling to Greece under the guise of being tourists, Falco and Helena visit the country’s classic sites in order to investigate the suspicious goings-on and shady dealings of Seven Sights, a fly-by-night travel agency. What begins as a risky expedition becomes sinister when Aulus, too, goes missing.