Decius Caecilius Metellus the Younger has been enjoying an easy exile on Rhodes, banished by his family for his incorrigible trouble-making. But he is recalled to Rome when they suddenly have a need for his peculiar skills. Metellus Celer, head of a politically powerful family, has been poisoned, and the most likely candidate for the deed is his infamous wife, Clodia. A simple case of a wife disposing of an incovenient husband. It happens every day. But nothing is ever simple about murder among Rome's ruling classes. Poisoning is more serious than, say, stabbing or strangulation. Poisoning involves the laws against witchcraft. There is a secret, forbidden cult of the old Earth gods that flourishes right alongside the official State cult of the Olympians, and Decius discovers that some very highborn people are involved in it. A trial of Coldia for poisoning could embarrass some of Rome's most important families.

And there is a further complication. Decius thinks Clodia is innocent (of this particular murder, anyway) and is forced into an uneasy alliance with her brother, Clodius, darling of the plebs and his sworn enemy. Life is never simple for the servant of the Senate and People of Rome.