Catherine wakes in the morning and quickly checks the manuscript she discovered the previous night. To her dismay, it does not contain some secret journal or terrible confession, but only washing bills. Catherine is ashamed, and scolds herself for her letting her wild imagination get the better of her. She dresses and goes down to breakfast, meeting Henry there. They discuss flowers and other things until General Tilney comes in. He talks about his breakfast table set, and tells Catherine that he hopes she will soon have the opportunity of selecting one of her own. Catherine is the only person in the room that does not understand the General's hint: he wants her to marry Henry.
After breakfast, Henry leaves for Woodston for a few days. The General shows Catherine around the Abbey (along with Eleanor). To Catherine's consternation, everything is modern. The General has even rebuilt an entire wing of the Abbey, making it new. On the way back into the Abbey, Eleanor decides to take Catherine on an alternate route through a gloomy path. This path is much more appropriate to a Gothic novel than the rest of the Abbey is. The General does not like the path, and chooses a different one. Eleanor tells Catherine that she used to enjoy walking down the path with her mother, and Catherine asks many questions about the late Mrs. Tilney. Catherine quickly begins to grow suspicious of the General. When their walk ends, Catherine looks somewhat troubled, and the General blames it on the path Eleanor chose. He sends them inside and warns Eleanor not to show Catherine any more of the house until he returns, a command that interests Catherine.
The General returns after an hour. Catherine thinks his walks are signs of a troubled conscience. Her imagination is running away with her, and she suspects the General of killing his own wife. The General shows Catherine around the rest of the house, except for one small area. This makes Catherine intensely curious about the forbidden area, especially when she learns that General Tilney's late wife had a room beyond the forbidden doors.
Catherine questions Eleanor about her mother, and discovers that she died suddenly of an illness while Eleanor was away. Catherine sees this as a confirmation of her suspicions. She begins to view everything the General does as more evidence of his troubled conscience. She even imagines that Mrs. Tilney is still alive, locked somewhere in the basement of the Abbey. She decides to stay awake until midnight to see if Mr. Tilney goes down to the dungeon where Catherine suspects he is keeping his wife. Catherine falls asleep by half past eleven, despite her plans.
In these chapters, Austen parodies Gothic novels and also captures Catherine's existence between emerging powers of perception and youthful naïveté. Catherine is expert at reading books, so when she begins to read people, she relies on her novel-reading expertise. She enters Northanger Abbey looking for a dark secret, but the Abbey turns out to be ordinary. Still, Catherine has never read about an abbey that lacks a dark secret, so she invents one for Northanger Abbey. Where Catherine has been remiss before in her efforst to understand people, she now reads too deeply into one person—the General—which results in a wild conclusion. Catherine up her mind about the General's guilt, and then begins to interpret his every action as more evidence of his guilt.
The General's grumpy nature and odd habits lend themselves to a negative interpretation of his character. However, Catherine never asks herself what motivation might cause the General to kill his wife. Henry is gone during these chapters, so the only person Catherine can get information from is Eleanor. Eleanor does not guess Catherine's suspicions. She would not think Catherine capable of such a horrid thought. Henry, in contrast, would see through Catherine's clumsy, prodding questions immediately.
When Catherine starts to think that Mrs. Tilney might still be alive and living somewhere in the basement of the Abbey, we begin to realize that Catherine is getting a bit carried away. At this point, Austen employs continual free indirect discourse, narrating the story in a tone that reflects what Catherine is thinking or feeling. In Chapter VIII, for example, after General Tilney tells Catherine he will be up all night writing pamphlets, she thinks, "To be kept up for hours, after the family were in bed, by stupid pamphlets, was not very likely." It is as if the narrator transcribes Catherine's thoughts. This technique gives Austen more space to work with her story than a first-person narrator would, because she can move the free indirect form from one character to another, and can use it to great effect in making fun of superficial characters such as Isabella.