Heretics of Dune

Set roughly 1,500 years after God Emperor of Dune, Heretics of Dune opens the second arc of Herbert’s saga. Humanity has returned from the Scattering carrying new powers and new enemies. Sheeana — a young girl who can command sandworms — becomes the focus of a struggle between the Bene Gesserit, the Tleilaxu, and the violent Honored Matres.

Herbert planned Heretics and Chapterhouse as the opening of a third trilogy he did not live to complete.