Previously managed by House Atreides' longtime enemies, the Harkonnens, Arrakis is an inhospitable desert planet plagued by giant sandworms, and the only known source of melange, the valuable drug at the center of the galactic empire's economy. Leto suspects treachery on the part of Padishah Emperor Shaddam IV, but cannot refuse the assignment. Soon the Baron Harkonnen launches an attack, his forces secretly bolstered by Shaddam's fierce Sardaukar warriors and aided by Leto's own trusted Suk doctor, Wellington Yueh. Coerced by the Baron to save his wife from torture, Yueh disables the shields of the Atreides fortress and delivers a drugged Leto to the Baron, but also provides Leto with a false tooth filled with poison gas. Leto bites down on the tooth in the Baron's presence, but the gas only manages to kill Leto and the Baron's twisted Mentat, Piter De Vries. Jessica is drugged, bound and gagged to prevent her using her powers. The Baron orders that she and Paul be disposed of in the desert. Thanks to supplies left by Yueh, Paul and Lady Jessica escape into the desert and find refuge with the native Fremen. They take advantage of the legends planted there by the Bene Gesserit's Missionaria Protectiva, which practices religious engineering. Jessica casts Paul as the "Lisan al'Gaib", the messiah, and herself as the Reverend Mother who shall bring him, even though she has not yet experienced the Bene Gesserit spice agony that transforms an acolyte into a full Reverend Mother. Jessica is also revealed to be the secret daughter of the Baron Harkonnen himself.