Chapterhouse Dune picks up the story as the Bene Gesserit sisterhood faces a dangerous enemy that is sweeping in from outside the known galaxy. Their base on the planet Chapterhouse is threatened, and they work to gain new allies and to preserve their knowledge and way of life.
The book follows Mother Superior Darwi Odrade and others as they try to adapt, even as old rivalries and secrets complicate matters. It is a reflective final novel in the series, concerned with survival, change and the uses of faith and power.