Alessandro--whose mother was reported to have been a black slave, the reason for his swarthy complexion and nickname, Il Moro--took advice from no one, living for his own pleasure, his motto being ''They made me duke, so I'll enjoy it!'' By enjoying it he meant wandering the streets at night fully armed, pushing aside anyone in his way, looking for a fight he was destined to win for the simple reason that he had barred the carrying of a sword or a firearm, both of which never left him, nor did his dagger. And he had reason to fear, as the nobility of Florence wanted him, the city's new duke, replaced by legitimate blood, noble blood. He had gained power at age 19 and had by now fully tasted every perversion, so that what was left was taking the hymen of those who still had one, notably nuns, and that of those who kept guard over theirs, virtuous women. He liked his boys too, for quick, easy couplings, heated and virile. His favorite companion was his cousin Lorenzino with whom he shared his bed and more when not extinguished from a night of whoring. And when he awoke with a lustful urge, Lorenzino was always conveniently spread out, naked, at his side. This is how Cellini had caught them many times, as the artist was permitted to come and go as he wished, and as Alessandro had no modesty and no need to hide his vices, Cellini was aware of everything that went on. ''Meanwhile I went on making the Duke's portrait and oftentimes I found him napping after dinner with that Lorenzino of his, '' wrote the artist in his autobiography.No one knows why Lorenzino turned against Duke Alessandro, aided by a professional assassin, Scoronconcolo. In his play, Lorenzaccio, Musset writes that Lorenzo wanted the duke dead so that Florence could become a Republic again. Others suggest that he was just jealous of the duke's powers and privileges. Because Duke Alessandro was so unpopular, he was never without his body armor, weapons and guards. But Lorenzino told him that he had found a Florentine lady of exceptional beauty and, especially, ironclad chastity. Lorenzino would bring her to the duke, and from then on it was up to the duke to prove that he could triumph over virtue. Lorenzino convinced the duke to dismiss the guards for the night, to take off his armor and to slip naked into bed. From then on it was easy for Lorenzino to strike him in the stomach with a dagger, his hand over his mouth to smother his shouts, Scoronconcolo giving the coup-de-grâce by slitting the duke's throat from ear to ear. Afterwards he rode off to Venice, a glove covering a finger Alessandro had caught between his teeth and nearly bitten off. The events that led to Alessandro's assassination, and the destiny reserved for Lorenzino, are the subjects of this book.