Quintas Caecilias Metellus Celer, a relative of Decius and his family and the head of a powerful political family, has been poisoned, and his infamous wife Clodia is immediately suspected of disposing of her rather inconvenient husband. Not entirely convinced of Clodia's guilt, Decius delves into the intricacies of Rome's ruling class and discovers that a clandestine, forbidden witches' cult is inextricably intertwined with some very highborn people. A trial for Clodia would be most unwelcome as it could bring to light some well-kept secrets. To get to the bottom of the corruption that accompanies the intoxicating allure of this ancient city, Decius must form an uneasy alliance with Clodius, Clodia's brother and his sworn enemy, and be extremely careful not to step on any toes.