Decius Caecilius Metellus is happy. The weather is beautiful and he is standing for office (literally; standing, in the Roman Forum soliciting votes) with a sure chance of winning. And Caesar's ongoing dreary war is far off in Gaul. Decius is confident that another war looming over Rome, instigated by one Crassus against the Parthians (for no reason but possible worldly gain); will be voted down in the Senate. But the vote does not stop Crassus.

On the day he and his troops set out from Rome, the Tribune Ateius Capitus, leader of the opposition, shrieks an ancient and terrible curse over the huge crowd assembled -- a curse that frightens not only the man in the street but the highest Romans. When Ateius is murdered soon after, Decius, solver of past mysteries, has the ugly task of finding the killer. Fascinating details of Rome's mixed attitudes about the power of magic and the practice of rational politics illuminate this latest of Roberts's strong historical mysteries.