Florence, the 1560s. Lucrezia, third daughter of Cosimo de' Medici, is free to wander the palazzo at will, wondering at its treasures and observing its clandestine workings. But when her older sister dies on the eve of marriage to Alfonso d'Este, ruler of Ferrara, Modena and Reggio, Lucrezia is thrust unwittingly into the limelight: the duke is quick to request her hand in marriage, and her father to accept on her behalf.