The sworn enemy of the Atreides is House Harkonnen, commonly called the Harkonnens. In Frank Herbert’s Dune, the Harkonnens are one of the major noble houses of the Landsraad and have a long-standing feud with House Atreides.
The rivalry is intensified when Duke Leto Atreides receives control of Arrakis, taking over the planet’s lucrative spice operation from Baron Vladimir Harkonnen. The transfer is part of a political trap arranged by the Emperor, who secretly supports the Harkonnens with Sardaukar troops. The Harkonnens then launch a devastating attack that drives the Atreides from power.
The family is led by Baron Harkonnen, while his nephews Glossu Rabban and Feyd-Rautha play major roles in the story. A common mix-up is confusing the Harkonnens with the Corrinos, the imperial family, or the Bene Gesserit. “Harkonnens” is the correct plural form for the house and its members.