Generate a question that has the following answer: Padishah Emperor Shaddam IV for the following movie plot: In the distant future, the known universe is ruled by Padishah Emperor Shaddam IV. The most important substance in the empire is the drug known as melange or "the spice". It has many special properties, such as extending life and expanding consciousness. The most profitable and important of its properties is its ability to assist the Spacing Guild with folding space, which allows safe, instantaneous interstellar travel. Sensing a potential threat to spice production, the Spacing Guild sends an emissary to demand an explanation from the Emperor, who confidentially shares his plans to destroy House Atreides. The popularity of Duke Leto Atreides has grown though the empire, and he is suspected to be amassing a secret army equipped with sonic-based weapons, which Emperor Shaddam sees a potential threat to his rule. Shaddam's plan is to give House Atreides control of the planet Arrakis (also known as Dune), the only source of spice. Once installed on Arrakis, he intends to have them ambushed by their longtime archenemies, the Harkonnens, with assistance from the Emperor's elite troops, the Sardaukar. The Guild Navigator also commands the Emperor to kill Duke Leto's son, Paul Atreides, a young man who dreams prophetic visions of his purpose. The execution order draws the attention of the Bene Gesserit sisterhood, as Paul is tied its centuries-long Bene Gesserit breeding program which seeks to produce the universe's superbeing, the Kwisatz Haderach. Before he leaves for Arrakis, Paul is tested by the Bene Gesserit Reverend Mother Gaius Helen Mohiam by being forced to place his hand in a box which induces excruciating pain. To her suprise, he passes the test to Mohiam's satisfaction. Meanwhile, on the industrial world of Giedi Prime, the sadistic Baron Vladimir Harkonnen tells his nephews Glossu Rabban and Feyd-Rautha about his plan to eliminate the Atreides by manipulating someone in House Atreides into betraying the Duke. The Atreides leave their homeworld Caladan for Arrakis, a barren desert planet populated by...
Who rules the known universe?