Now available on Netflix, Denis Villeneuve's adaptation of Frank Herbert's landmark work Dune starring Javier Bardem, Rebecca Ferguson, Oscar Isaac, and Timothée Chalamet was a huge success. Even the biggest Dune fans, however, will surely have a lot of questions after they watch the movie. There's much we don't know about Arrakis' sandworms, and even what we do know likely isn't the full picture, as the surface of Arrakis is vast and only so much is observable with regard to the planet's apex predator. Speaking of, what do these things eat exactly? The simplest and straightforward answer is "whatever they feel like."

They're massive, stacked with teeth, and they make the fictional universe of Dune keep turning. The titanic sandworms of the planet Arrakis are its most distinguishable feature alongside the hardy Fremen people and the spice Melange, the all-important resource in Herbert's deep sci-fi franchise. The worms of Arrakis are crucial components in the creation of the spice, which means aspiring power brokers must ensure their survival above all else. However, much of what is known about the worms in both the written and cinematic iterations of Dune is partially shrouded in mystery. You would think a creature several dozen meters long would be easier to observe, but the creatures are prone to burrowing underground as quickly as they appear.

What Role Do 'Dune's Sandworms Play?

Ordinarily, sandworms on Arrakis spend most of their time gobbling up sand that comprises the nearly endless dunes covering the planet. In doing so, they are able to feast on creatures known as sand plankton, microscopic creatures that devour leftover traces of the spice scattered across the Arrakeen sands. Worms are also known to consume dry components of the planet's crust, creating a diet of mostly sedimentary and inorganic material. However, that doesn't mean sandworms don't occasionally get a nice treat.

The harvesting of the spice by multiple Great Houses over the course of thousands of years in order to supply the Spacing Guild with the necessary resources for their navigators to fold space-time and make space travel across the Imperium possible. Off-worlders don't exactly have the reverence for sandworms that the native Fremen have, and tend to view them as pests to be avoided while harvesting spice on the planet's surface. With so many spice harvesters rumbling along accompanied by humans that aren't adept at the Fremen sand walk, vibrations abound on the planet and such disturbances attract worms in the area.

Don't Give 'Dune's Sandworms Water!

During particularly botched spice harvesting operations, worms are known to consume entire spice harvesters and anybody unlucky enough to be around them when the massive maws of the worms enclose around them. Thanks to sandworms' gastrointestinal tracts essentially being a massive blast furnace, they can easily swallow and digest most materials and organisms. However, there is one particular thing that sandworms must avoid under the threat of a painful death: Water.

Even in incredibly small amounts, water is fatal to the sandworms of Arrakis. Water that enters a worm's body causes metabolic acceleration to the point of organ failure. This is obviously best avoided for the worms, but their death via water also serves a very important purpose. The bile that results from the death of a worm's consumption of water results in a substance known as the Water of Life, which is used in ascendancy rituals both by the Fremen and the Bene Gesserit to accelerate an individual's awareness spectrum. Well, if they survive, that is. The Water of Life is highly toxic and only those with perfect control of their mind and bodies are capable of consuming it without meeting an agonizing end. When it comes to Dune's most iconic creature, they can chow down on just about anything. Just don't expect them to have a drink on the side.

The Big Picture

• Sandworms of Arrakis are essential for the production of the spice Melange and their survival is crucial for those seeking power.
• Sandworms primarily feed on sand and sand plankton found on Arrakis, but they also consume other dry components of the planet's crust.
• Sandworms are attracted to vibrations caused by spice harvesters, and in some cases, they consume the harvesters and people around them. Water is lethal to sandworms, but their consumption of water creates a substance called the Water of Life used in rituals.