Cesare burns Constanzo's palace - and the Cardinal with it - in order to contain the plague, while Micheletto is love struck with the beautiful young Pascal. Lucrezia, aware that the political wind has changed towards France and away from Naples, seeks a Neapolitan power base for herself and her family. There are two candidates to replace Ferdinand as King: arrogant and hostile Prince Raphael and kind and friendly Prince Frederigo. When Frederigo is apparently poisoned and almost dies, Lucrezia finds evidence of Raphael's guilt and blackmails Raphael into giving up his claim. Her ally, Frederigo, is crowned King. But has she made the right choice?