The world of Dune is dense with locations, houses, creatures, and names that can be hard to remember ( and even harder to pronounce). As we continue to pore through Frank Herbert’s seminal sci-fi novel for Nerdist Book Club—and as we prepare for the December release of Denis Villeneuve’s film adaptation—we’re visiting many of the terms from Dune on a micro-level. And one term you absolutely must be familiar with in the book and upcoming film: Fremen.

The Fremen are a grouping of people who are integral to the plot of Dune and to the journey of central character Paul Atreides. Here is everything you need to know about them.

Denis Villeneuve directs Javier Bardem in DuneWarner Bros/Legendary

The Fremen live on Arrakis

Though they are not native to the desert planet of Arrakis, the Fremen are a group of humans who live in the dangerous trenches of the world. They live in communities known as “sietches,” which are tribes headed by “naib” leaders—who come into power after challenging and beating the former leader, and are known as the strongest member of their particular group. Each sietch also has a Sayyadina, the Fremen version of a Bene Gesserit, or a wise woman trained in magic who assists in the community in spiritual guidance.

The Fremen are a somewhat savage tribe. They choose to live outside of the cities of Arrakis and in the wilderness of the desert, where they face the dangerous sandworms and duke it out amongst themselves. They use trial by combat as their main judicial system and wear stillsuits that assist with water retention so they can exist in the desert conditions. The Fremen have many traditions and religious beliefs; they bear sacred weapons known as “ crysknives” and regard the sandworms as godlike creatures.

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Their origins before that are mysterious

Much of the history of the Fremen prior to their arrival on Arrakis is lost. It is believed that Arrakis was the final stop on a migration from the planet Poritrin, but even that information is tenuous. The fact that their origins are so murky is especially curious given how keen they are on the oral history of their tribe on Arrakis. It seems that perhaps they are a people who want to forget where they came from and see their arrival on Arrakis as the rebirth of their people.

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They are addicted to spice melange

The Fremen are known for having “leathery” tan skin and bright “blue within blue” eyes, meaning every portion of the eye is stained with the color. This is due to their ingestion of spice melange, a powerful substance only found on Arrakis (and produced by the lifecycle of the sandworms). Because the Fremen live off their own water storage and inhale and live within the harsh conditions of Arrakis, they ingest copious spice melange—which, in addition to keeping them alive, also increases many of their combat and prescient abilities. Their blue eyes are known as the “ Eyes of Ibad.”

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They are integral to Paul Atreides’ journey

The main character in the first Dune novel is Paul Atreides, who comes to the planet Arrakis with his family to oversee the harvest of spice. Paul is drawn to Arrakis even before his arrival, and particularly to the Fremen. He has dreams about them, specifically of a Fremen woman named Chani. Without getting into spoilers, certain events occur that lead Paul directly into a Fremen sietch, a fateful meeting that determines the future of the Known Universe and the world of Dune as we know it.

Now that you’re fully acquainted with the Fremen, be sure to join us as we wrap up our discussion of Dune over at Nerdist Book Club! See more information here.

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