Poisoner! The bellowed accusation strikes into silence all those in Lucrezia Borgia's audience chamber. Lucrezia has fled Rome to a loveless marriage with Alfonso, heir to the duke of Ferrara, to escape the rumors that she is utterly depraved---incestuous, a lecher, a poisoner. To her delight she is warmly welcomed in Ferrara, by the duke, by his court, by the people, indeed by everyone except her husband. And then, after only six weeks of basking in the warmth of general approval, Alfonso rushes into her apartment and accuses her of poisoning Bianca Tedaldo, one of her ladies in waiting and mistress to Alfonso.