From several ships landing on Arrakis to the end of the novel
Several ships land behind Arrakis’s rocky shield wall. The emperor has come to Arrakis, along with Baron Harkonnen and five legions of Sardaukar. Stilgar and Paul’s plan is to wait until a great sandstorm strikes, and then break the shield wall with atomic weapons. Next, the Fremen will blast the noses off the spaceships so that the vehicles cannot take off. Then the Fremen will rush the Sardaukar, while the people of Arrakis rise up against the emperor and his forces.
When the sandstorm hits, Halleck blows up the shield wall. As Paul and his soldiers prepare for battle with the Sardaukar, they receive a message from Sietch Tabr: it has been raided, and many of its inhabitants have been killed, including Paul’s son, Leto. Alia has been captured. Chani and Jessica were hiding out closer to the city, so they were not at Sietch Tabr during the raid.
Meanwhile, inside the emperor’s ship, just before the shield is attacked, the baron and the emperor discuss their plans. Feyd-Rautha and Rabban are also members of the party, though they are outside the ship, scouting the perimeter. The emperor presents Alia, whom his men have captured, to the group. The emperor is enraged since only a handful of his Sardaukar got away from old men, women, and children, as the Fremen are such excellent fighters.
The emperor’s truthsayer, or one who detects sincerity, is the Reverend Mother Gaius Helen Mohiam. Mohiam calls Alia an abomination—Alia has the consciousness of all reverend mothers of the past; therefore, she knows all of Mohiam’s memories and is inside her mind. Just as the emperor is threatening Paul, the Fremen strike, destroying the shield wall. Alia kills the baron—who is her grandfather—with her gom jabbar and escapes. The emperor hears reports that the Fremen have breached the shields of his ships and have broken the ships’ noses so they cannot lift off. Shocked, the emperor and his troops see the Fremen riding toward them on dozens of giant sandworms. The Fremen soon defeat the Sardaukar, and Paul resumes his place on the throne at the Arrakeen governor’s mansion. Paul sends a Sardaukar captive as a messenger to the emperor to discuss the terms of the emperor’s surrender. Paul, however, is worried: he still sees the jihad ahead of him. He now accepts the fact that he is the Kwisatz Haderach.
Chani and Jessica arrive, and then the emperor and his entourage appear. Paul asks Thufir Hawat to come forward. The baron secretly administered poisons to Hawat, and Hawat is near death. The emperor has given Hawat a poisonous needle to use to kill Paul, but Hawat refuses and dies in Paul’s arms.
The emperor threatens to command the House of Landsraad ships to attack the Fremen, but Paul orders the representatives of the Spacing Guild to force the House of Landsraad ships to leave. Paul threatens that if they do not leave, Paul will destroy all the spice on Arrakis, robbing the Guildsmen of their supply. The Guildsmen obey Paul’s orders, angering the emperor, who is powerless without the support of the Guild. Paul then turns his attention to the Reverend Mother Mohiam, telling her that he refuses to do the bidding of the Bene Gesserit or to be the cause of the jihad, which even the Bene Gesserit do not realize is their ultimate goal.