Rome, 1656. In the shadowy backstreets of the Eternal City lies an apothecary – a place for women to take their heartbreaks and troubles. Herbs for childbirth. Tarot readings to tell their fortunes. An undetectable poison that can kill in four drops. Alongside her circle of female poisoners, Giulia Tofana dispenses her deadly potion to free the downtrodden women of Rome from their abusive husbands. But even in a time of Plague, it does not go unnoticed when the men of Rome begin to fall like flies. With a newly-elected Pope hell-bent on ridding the city of heretics and witches, and the Holy Office of the Inquisition on her tail, Giulia is in more danger than ever. How far will she go for the women who need her help?