|Cardinal Versucci, one of those implicated in the fictitious anti-Borgia conspiracy by cardinal DeLuca's false confession and summarily stripped of his office, titles and riches, decides to make an impressive exit: after stealing Vatican fortune, he sets the Treasury ablaze to cover his tracks, yet Rodrigo's troubles don't end there. A report commissioned by Cesare informs the Pope that his army's strength is significantly diminished and nowhere near ready to counter Caterina Sforza's forces. After denying Cesare the command of the papal army yet again, Rodrigo orders Cesare to go to Naples to finalize Lucrezia's wedding contract and inspect the Neapolitan armed forces' viability as a military ally.|
Cesare's journey to Naples and Micheletto's spying work ascertains a sad truth for the Borgia son: the Neapolitan army is also weakened, despite the arrogant King Ferdinand's attempts at convincing Cesare otherwise, and Naples in general is much more of a beggar than an equal ally to Rome. That fact, coupled with Ferdinand's obstinate refusal to accept Giovanni, Lucrezia's bastard son, in the Neapolitan court and Alfonso of Aragon's indecisiveness in the matter drives Cesare furiously questioning his father's choice of an ally by marriage.
Meanwhile, back in Rome, Rodrigo meets with the ambassador of the new French king, Louis XII who seems like a potential friend to the Roman papacy. The Pope is assured that if Louis can be granted a divorce from his ugly and barren consort, the French will be in Rome's debt. Rodrigo and Cesare sense the great opportunity and the father orders the son to leave for France soon after Lucrezia's wedding bearing the gift of a papal brief of annulment, which is not to be traded lightly: Rodrigo wishes not only French favour but also a French noble bride for his son, in order to spread his tentacles from Naples to France.
Rufio, Caterina Sforza's agent, meets with Vitelli, Baglioni, Colonna and Orsinis in another attempt to convince them to join Sforza's side by showing them the report that proves the papal army's pitiful state but the Italian noblemen aren't yet fully ready to choose a side.
Lucrezia is informed that the King of Naples has yet to be convinced about the need for her son's presence in the Neapolitan court and that Cesare's future engagement to France, Naples' mortal enemy, could endanger her marriage which strains her relationship both to Alfonso and to Cesare, even if the two siblings share a passionate kiss soon after speaking about this predicament.
Just before Lucrezia's wedding, Cesare informs Rodrigo that King Ferdinand has decided to put on a show of strength and invited their loathed opponent Caterina Sforza and every important Romagna lord to the wedding as proof of Naples' ability to fraternize with other allies besides Rome. Cesare uses a seating plan as a board to clarify Borgia allies and enemies and places Alfonso of Aragon in the middle, unsure of his true allegiance. Rodrigo forbids Cesare from showing any kind of irritation with the King of Naples' decision and welcomes all his enemies to Rome: in an attempt to confuse the Pope, Caterina Sforza even bows and kisses the papal ring.
During the wedding, an altercation between Cesare and Roberto Orsini breaks out just as Caterina is informed of the Italian noblemen' terms for joining her. Lucrezia and Alfonso leave early to consumate their marriage but Alfonso notices Cesare's clear doubt of his true obedience and feeling offended and betrayed, lividly denies Lucrezia's sexual advances, leaving her alone and feeling unwanted. As Alfonso is crying in a room, feeling used both by his cruel uncle, Ferdinand of Naples, and his soon-to-be family, Lucrezia swiftly turns to Cesare for consolation, who is soon seduced and gives in to his long lust for his sister and the two siblings engage in incestuous fornication.