There was a supper at the Vatican. Alfonso made an elegant toilet, and about ten o'clock at night prepared to go from the quarters he inhabited into those where the pope lived; but the door which separated the two courts of the building was shut, and knock as he would, no one came to open it. Alfonso then thought that it was a simple matter for him to go round by the Piazza of St. Peter's; so he went out unaccompanied through one of the garden gates of the Vatican and made his way across the gloomy streets which led to the stairway which gave on the piazza. But scarcely had he set his foot on the first step when he was attacked by a band of armed men. Alfonso would have drawn his sword; but before it was out of the scabbard he had received two blows from a halberd, one on his head, the other on his shoulder; he was stabbed in the side, and wounded both in the leg and in the temple. Struck down by these five blows, he lost his footing and fell to the ground unconscious; his assassins, supposing he was dead, at once remounted the stairway, and found on the piazza forty horsemen waiting for them: by them they were calmly escorted from the city by the Porta Portesa. Alfonso was found at the point of death, but not actually dead, by some passers-by, some of whom recognised him, and instantly conveyed the news of his assassination to the Vatican, while the others, lifting the wounded man in their arms, carried him to his quarters in the Torre Nuova. The pope and Caesar, who learned this news just as they were sitting down to table, showed great distress, and leaving their companions, at once went to see Alfonso, to be quite certain whether his wounds were fatal or not; and on the next morning, to divert any suspicion that might be turned towards themselves, they arrested Alfonso's maternal uncle, Francesco Gazella, who had come to Rome in his nephew's company. Gazella was found guilty on the evidence of false witnesses, and was consequently beheaded.
But they had only accomplished half of what they wanted. By some means, fair or foul, suspicion had been sufficiently diverted from the true assassins; but Alfonso was not dead, and, thanks to the strength of his constitution and the skill of his doctors, who had taken the lamentations of the pope and Caesar quite seriously, and thought to please them by curing Alexander's son-in-law, the wounded man was making progress towards convalescence: news arrived at the same time that Lucrezia had heard of her husband's accident, and was starting to come and nurse him herself. There was no time to lose, and Caesar summoned Michelotto.