My views Plot In the distant future, Duke Leto Atreides is assigned by the Padishah Emperor Shaddam IV to replace Baron Vladimir Harkonnen as the fiefholder of Arrakis , a harsh desert planet and the sole source of " spice ", a valuable psychotropic substance that imparts heightened vitality and awareness. Spice is also key to interstellar travel , giving Spacing Guild Navigators the ability to guide starships to traverse space instantaneously and safely. Emperor Shaddam, fearful of Leto's rising power, plots for House Harkonnen to retake Arrakis, secretly aided by his Sardaukar troops, and destroy House Atreides. Leto is suspicious of the Emperor but weighs the risks against the power of controlling Arrakis and making an alliance with its mysterious natives, the Fremen . Leto's concubine , Lady Jessica , is an acolyte of the Bene Gesserit —an exclu...