Now there seems to be real danger that Valmont's plans will fail. The Présidente de Tourvel writes to Madame Volanges (Letter Thirty- seven) to tell her that she has determined that the only way to end her predicament without a scandal is to ask the Vicomte to leave Madame de Rosemonde's estate.
Back in Paris, the Marquise de Merteuil has received a package of Tourvel's letters from Valmont, though she claims to be more interested in the eventual corruption of Cécile Volanges than the seduction of the Présidente. Her Letter Thirty-eight to Valmont contains some news about Merteuil's progress in educating Cécile about the ways of the world.
As for Cécile, she writes to Sophie (Letter Thirty-nine) to report on her latest tribulations with the Chevalier Danceny and her appreciation of the way the Marquise has taken her under her wing.
Letter Forty contains both the Vicomte's letter to the Marquise de Merteuil and a letter sent to him by the Présidente, which he wants the Marquise to read along with his own. His news is that Tourvel has asked him to leave her aunt's estate, and that he has been (as yet unsuccessfully) searching her rooms to try and find all her correspondence so that he can figure out what to do.
In Letter Forty-one the Présidente de Tourvel asks the Vicomte to leave Madame de Rosemonde's estate. She also mentions that, aside from the Vicomte's amorous harassment, advice from friends about the Vicomte's bad reputation has persuaded her that she should leave.
Letter Forty-two is the Vicomte's response to the Présidente's command. He says he will go, but on two conditions: that Tourvel tell him who it was who wrote to her about his bad reputation, and that she allow him to correspond with her while they are apart.