After the wager that lies at the heart of Dangerous Liaisons, Merteuil – Seduction sets out to “adjust” some of the novel’s central elements — and once the exchange of letters (the backbone of the original text) is largely abandoned, something essential is inevitably lost.

In this version’s manipulative triangle, Rosamunde is not only aware of the challenge between Isabelle and Valmont but actively participates in it. She is the one who reports on the viscount’s whereabouts: since Madame de Tourvel did not respond to his letters, Valmont went after her — with Rosamunde’s direct support and interference. But Madame de Tourvel flees from him, which, among the libertines, becomes a source of mockery, especially for Gercourt. Rosamunde assumes Isabelle will also laugh and relish this “victory.” Soon, Valmont would be forced to give up.

Isabelle’s reading is interrupted by Cécile, and the two discuss Valmont and Madame de Tourvel. “Her pride is unbearable,” Isabelle complains, frustrated that she feels no satisfaction in Valmont’s defeat. She knows it is merely a façade and decides to “help” him. She does so by manipulating the innocent De Tourvel, suggesting that, “for her,” she will make the confession she has always denied her husband.

In their conversation, Isabelle praises Valmont as a man, but Madame de Tourvel wants to know his qualities as a lover. The marquise does not fall into the trap, and the two — mutually jealous — exchange sharp barbs. Isabelle questions De Tourvel for “playing the saint,” sacrificing basic pleasures. The response is brutal: today the marquise is beautiful and, by playing “the whore” — as the title bluntly puts it — she wins immediate battles; but she will lose the war when she grows older.

At home, Rosamunde is surprised by a visit from Gercourt, who claims he wants reconciliation. In truth, he seeks her help and attempts to seduce her again to obtain it. His demand is that Rosamunde break with Merteuil — but she sees Isabelle as her own daughter. Frustrated, Gercourt resorts to physical violence when he does not get what he wants. Rosamunde is deeply shaken.

Isabelle’s strategy to break De Tourvel takes a strange turn: she brings Danceny to play music and provoke the repressed judge’s wife. Madame de Tourvel is on the verge of breaking her vows — so obvious that the Marquise de Merteuil actually orders Danceny to knock on her rival’s bedroom door and… well, “help her.”

Danceny cannot go through with it: he loves Cécile. The plan nearly works, but fails. Rosamunde, meanwhile, grows increasingly irritated by Isabelle’s obsession with De Tourvel, especially as she neglects the urgent need to defend herself against Gercourt.

In another strategic shift, Isabelle lays her cards on the table with Madame de Tourvel: she claims she has won and no longer wishes to play. Valmont wagered that he would seduce her because, in truth, he genuinely loves De Tourvel — and is ashamed of it. “He wants me because he loves you,” De Tourvel replies, following a twisted but sincere logic. When she is alone, Isabelle laughs. The move is precise: De Tourvel believes her and will no longer resist Valmont.

Now positioning herself as a master of seduction, Isabelle advises Cécile to keep Danceny merely as a lover and to stop idealizing him. She notices that Rosamunde seems different. Without revealing that she was assaulted, Rosamunde comments that Gercourt intends to go directly to the king and demand Merteuil’s head. The alternative would be to crawl back, ask her husband for help, and admit that she misses him. Isabelle refuses to relinquish her freedom and, lacking the full picture, interprets Rosamunde’s behavior as cowardice.

Madame de Tourvel seeks out Valmont and tells him she knows about the wager. He does not retreat: he refuses to lie to her. The two kiss. Farewell, little saint.

Even if Isabelle were to reconsider Rosamunde’s advice, the choice is ripped away from her: she discovers she is now a widow. The foolish Marquis de Merteuil has died — accidentally. Yes, you read that correctly. Isabelle laughs, delighted, and summons Rosamunde.

The next morning, Madame de Tourvel lies awake, pensive in bed. Valmont leaves her to offer his condolences to Merteuil and recount the details of his night of passion. He reveals that even while in love, his thoughts were fixed solely on Isabelle. She rejects his advances: the letter breaking definitively with De Tourvel is still missing. He writes it — but somehow, nothing between them feels the same anymore. De Tourvel is devastated when she receives the letter.

Rosamunde goes to see Gercourt. Everyone already knows about Valmont’s “victory” — but how? The real issue, however, lies elsewhere: he has proof that Rosamunde was involved in arranging her nephew’s marriage and demands that she testify against him. Gercourt’s goal is to strip Isabelle of her title. Technically, he is right: Isabelle was indeed a bigamist, thanks to Valmont’s recklessness. Still, the cruelty lies in blackmailing Rosamunde into betraying both her nephew and Isabelle.

Valmont then receives an unexpected visitor: Cécile, sent by Isabelle to pay the wager in her place. He accepts. Isabelle weeps alone.