Fifteen hundred years after the death of the God Emperor, the Bene Gesserit Sisterhood and the powerful Honored Matres—a mysterious force returning from the outer darkness—compete for control of the galaxy and the precious spice. At the center of the conflict is young Sheeana, a girl on Arrakis who can command sandworms, and a ghola of Duncan Idaho created to serve as a weapon. A fast-paced entry in the saga exploring the nature of sexuality, power, and institutional control.