Osmond is angry with Isabel for spending so much time with Ralph; Isabel knows that Osmond wants to deny her any freedom of thought, and he knows that Ralph encourages her freedom. Isabel continues to see Ralph, who is clearly dying; but she tries to limit the time she spends with him to avoid conflict with her husband. Isabel meets Ralph and asks him about Lord Warburton's feelings for her. After some joking evasion, Ralph acknowledges to Isabel that Warburton is not in love with Pansy—he is in love with Isabel. As Ralph chuckles about the situation, Isabel breaks down and tells Ralph that he is "no help."
With this emotional outburst, Ralph feels as though Isabel has reached out to him at last. He offers to listen to her problems and to try to help her, but Isabel closes herself off and tries to end the conversation. She tells Ralph that Warburton will simply drop the matter of his relationship with Pansy, which, since he has never proposed to her, will be acceptable. But Ralph tells her that Osmond will blame Isabel for Warburton's disappearance. Embarrassed, Isabel tells Ralph that he is cruel to her; Ralph offers again to listen to her problems and prove that he is kind. But Isabel hastily leaves.
Isabel goes to speak to Pansy, who tells her that her only desire in life is to marry Rosier. Trying once more to be a dutiful wife, Isabel tells Pansy that her father does not wish her to marry Rosier and that she must do as her father wishes. Pansy agrees that she will not violate her father's orders and will remain single. But Isabel tells her that her father wishes her to marry Warburton. Relieved, Pansy says that Warburton will never propose to her; but she hopes that Osmond will not realize this, as having Warburton around will keep her father from finding another suitor for her. Isabel warns Pansy that her father is determined to see her married to a nobleman, and Pansy says that in her eyes, Rosier is noble.
Warburton does not call at the Osmonds' palazzo for four days. At last Osmond angrily accuses Isabel of having betrayed him and encouraged Warburton not to marry Pansy. At that moment, Warburton arrives at the palazzo. He tells Osmond and Isabel that he is returning to England and has come to say good-bye to Pansy. Osmond leaves, and Warburton says farewell briefly to Isabel and Pansy, who seems untroubled by his departure. After Pansy goes to bed, Osmond furiously accuses Isabel of trying deliberately to thwart him; he thinks that she intentionally convinced him to seek Warburton as a suitor for Pansy and then intentionally ruined the possibility of an engagement. Isabel is dismayed to discover the extent of his paranoia. Contemptuously, Isabel tells Osmond that he is wrong and leaves the room, feeling intensely sorry for Pansy.
Caspar Goodwood and Henrietta arrive in Rome just as Madame Merle and Rosier leave it—Rosier on a somewhat mysterious errand that no one can explain. Isabel thinks again of Merle's mysterious relationship with her husband, realizing that there is something extremely ominous about Merle. Henrietta asks Isabel whether she is miserable with Osmond, and Isabel admits that she is. But she says that she can never leave him, because she is too ashamed. Henrietta and Caspar befriend Ralph, and the three of them grow to like one another a great deal. But Osmond is deeply irritated to find that so many of Isabel's old friends have reentered her life. Still, he is bolstered by the arrival of Countess Gemini and the return of Madame Merle, who asks Isabel haughtily what she did to ruin Pansy's chances of marrying Warburton. Finally, Rosier returns to Rome; no one seems to know where he has been.
Ralph, who is in good cheer despite his increasingly frail health, eventually decides that he must return to Gardencourt. Henrietta and Caspar insist on going with him, the latter at Isabel's insistence. (Isabel hopes that Caspar can look after Ralph; Caspar believes that Isabel is bored with him.) Before they leave, Countess Gemini foolishly tells Henrietta that Isabel and Warburton had been having an affair. Annoyed, Henrietta contradicts her, but the Countess is quite sure of herself. When Henrietta tells Isabel that she is leaving for England, Isabel says that she is pleased—she feels that Henrietta and Ralph have been observers of her life; now she will be left alone with those who are actually involved in the sad little plot. Henrietta asks Isabel to vow that if things with Osmond get much worse, she will leave him. Isabel refuses; she says that she has failed in her marriage vows, and she will not make vows again.