Heretics of Dune by Frank Herbert is the fifth novel in the original Dune Chronicles, set approximately 1,500 years after the reign of God Emperor Leto II. Humanity has spread across the universe during the Scattering, and the planet Arrakis, now called Rakis, has returned to a desert environment where the sandworms and the spice cycle remain central to the fate of civilization. As powerful groups such as the Bene Gesserit, Bene Tleilax, and the mysterious Honored Matres compete for influence, the emergence of Sheeana, a young woman with the extraordinary ability to control sandworms, becomes increasingly important. The novel explores political power, religion, ecology, human evolution, genetic manipulation, sexuality, survival, and the continuing struggle to shape humanity's future.