It is set loosely in the thirteenth century around the First Barons' War, and follows the fortunes of the fictional De Morney family at the real Bungay Castle in Suffolk.

While Sir Philip is away, Roseline, Edwin, and Madeline explore the castle, which they suspect to be haunted, and find a gentleman, Walter, locked in a hidden apartment with his servant Albert.

Baron Fitzosborne realises that Walter is in fact his son, believed dead due to a scheme by his late wife and her brother.

Sir Philip's other two children, Bertha and Edeliza, make their own suitable marriages, as does the Baron, and the novel ends with optimism for everyone's futures.

[1] The real Bungay Castle was built and developed in the twelfth and thirteenth centuries before falling into disrepair after the death of Roger Bigod, 5th Earl of Norfolk.

Bonhôte was deeply familiar with Bungay Castle in Suffolk, and used this local setting to introduce more realism to her novel.

During her lifetime, the ruins of the castle had been partly converted into cottages for the rural poor, which she saw as a sad waste of a building which had once been highly desired by barons and kings.

[9] Like many eighteenth-century Gothic novels, Bungay Castle depicts convents as predatory institutions which imprison women against their will.

The reviewer praised Bonhôte's prose and described the hero, Walter, as "a being somewhat different from his predecessors in the dungeons," but found the plot too repetitive and the dialogue "very tame and insipid.