Deegan was a soldier for House Atreides when Duke Leto Atreides I and his household were ambushed on Arrakis by House Harkonnen in 10191 AG.
Entombed in the Shield Wall[]
Deegan's group of soldiers had been on patrol around the Atreides compound in Arrakeen during the attack by House Harkonnen. Gurney Halleck had ordered the contingent of soldiers to guard the storehouses of Atreides food, ammunition, and water supplies that had been stored in the Shield Wall. The Harkonnen forces had attacked the Wall, collapsed the ceiling of rock, and had buried the troops alive, sealing them in with an avalanche.
Deegan was relatively unhurt during the melee', as others, such as Elto Vitt had suffered massive injuries during the battle. Elto was considered by the men of his platoon to be a novice, someone who had received favortism because of his battle-hardened uncle, Sergeant Hoh Vitt.
The men realized their eventual fate, that they were sealed in permanently; when they attempted to release distrans bats out of the their cave into the Arrakis sky to carry the message that they were entombed underground, but the bats could not make it out of the rock formation. When the doomed troops realized their fate, Elto begged his uncle to tell them all stories of Caladan, their homeworld, in the ways of a Master Jongleur, a master storyteller.
Listening to the Master Jongleur[]
The Sergeant, who had been raised on Jongleur, told the stories of the fisherman of Caladan, and each of the men under Jongleur hypnosis, remembered their homeworld in each their own fashion. Avram Fultz, another of the soldiers, reminisced about eating a paradan melon, fresh from the sea. Elto remembered diving deep off the coast of the Southern Continent of Caladan. Deegan recollected seeing an elecran once, although was glad he never had contact with the fearsome monsters. Still entrapped within the avalanche of the Shield Wall, Deegan and the entire group of soldiers died of suffocation.
Later, as the cave was excavated by Fremen natives who realized that an entire troop of soldiers must lie in the buried cave, all of the men were found dead. But due to the storytelling of Hoh Vitt, each soldier was lined up with a joyous expression on their face, and each had died believing he had drowned on Caladan, doing the deed they were reminiscing about. Each of the soldiers lungs, including Deegan's, had sea water in them.