Northanger Abbey was written in the late 1790s, but published only posthumously. It is the story of a deliberately ordinary heroine named Catherine Morland. The book is divided into two parts. In the first, Catherine travels with family friends, the Allens, to Bath. There she meets two brother-sister pairs --- John and Isabella Thorpe, and Henry and Eleanor Tilney. Her own brother, James, joins them and becomes engaged to Isabella. Catherine is attracted to Henry, a clergyman with witty and unorthodox manners.

General Tilney, father to Henry and Eleanor, invites Catherine to visit them at home; this visit makes up the second half of the book. The General is at once solicitous and overbearing. Under the spell of the gothic novel she has been reading, Catherine imagines he has murdered his wife. Henry discovers this and sets her humiliatingly straight.

Catherine receives a letter from James telling her that Isabella has ended their engagement. General Tilney, upon returning from London, has Catherine thrown out, to make her own way home. It is eventually understood that Catherine and James had been mistaken for people of great wealth, but the situation has been clarified.

Henry is so outraged by his father's behavior that he follows immediately after Catherine and proposes marriage. They cannot proceed without his father's permission, but this is finally given in the happy madness of Eleanor's marriage to a viscount.