Catherine, Eleanor and Henry try to speculate about how Frederick Tilney will handle his apparent engagement to Isabella. The Tilney siblings are certain their father will not allow Frederick to marry Isabella because she is relatively poor, compared to the Tilneys. This bothers Catherine, since her family is hardly wealthier than Isabella's, but she takes comfort in how pleasant General Tilney has been to her.
The General proposes that the group take a trip to visit Henry at his Woodston home. Henry goes home to prepare for their arrival. In Woodston, Catherine is charmed by the modest house, the pleasant meadows, and the apple orchard. The General makes so many hints about the possibility of Catherine marrying Henry that even Catherine cannot miss them. She is sure of the General's intentions, but not of Henry's. The chapter ends with the group returning to Northanger Abbey.
Catherine receives a letter from Isabella, who says that Frederick Tilney abandoned Isabella to flirt with another girl before he even left Bath. Isabella clumsily tries to cover up her culpability and asks Catherine to write to James and help her get him back. Catherine angrily decides she will do no such thing, and renounces her friendship to Isabella in front of Henry and Eleanor. But she is still troubled about why Frederick Tilney acted as he did, and Henry suggests he just wanted to be mischievous. This annoys Catherine, although Henry points out that if she were truly concerned for her brother, she would be glad that he did not marry a person like Isabella.
During the trip to Woodston, Henry does not speak a word to Catherine. The General woos her more than Henry does. The General, who is always concerned with material things, believes Catherine must be convinced of the material gain she will make by joining their family. He talks about the improvements that could be made "by a woman's hand" throughout the Woodston house. He seems to have little faith in Henry's ability to attract Catherine, so he attempts to make Henry attractive in the only way he knows how—by showing off their wealth. By the end of the trip, even naïve Catherine cannot miss the General's intentions.
Isabella's letter is so blatantly manipulative that the narrator tells us "such a strain of shallow artifice could not impose even on Catherine." At the beginning of the novel, Catherine might have fallen prey to such clumsy manipulation. But now she has some experience, and she can see Isabella for who she is, a "vain coquette" who got what she deserved. Even more importantly, Catherine renounces her friendship with Isabella.
Catherine's brief argument with Henry about his brother marks a milestone in her path to adulthood. Catherine decides she does not like Frederick because he made mischief, and she partly blames him for James's break-up with Isabella. Henry puts more of the blame on Isabella. Catherine stands up to Henry, although she says it is right that he stands by his brother. In the sophisticated fashion of an adult, Catherine suggests that he is standing by Frederick not because it is just, but out of brotherly duty.