What’s Up With The Big Worms In Dune?

In films like The Empire Strikes Back, Tremors, and Beetlejuice, giant sandworms have long been sold to audiences as a terrifying threat. But the granddaddy of them all is Shai-Hulud, aka the big worms in Dune — a sandworm so iconic that Fatboy Slim dedicated an entire verse to them in “Weapon of Choice.” You’ve read about them in Frank Herbert’s bestselling novel. You’ve seen them on screen in David Lynch’s oft-maligned — but actually not terrible — 1984 film adaptation. Now, after Denis Villeneuve’s Dune brought them back in 2021, it’s time to dig in. Here, everything you need to know about the big worms in Dune. Major spoilers for Dune follow.

The sandworms play a critical role in Frank Herbert’s novel — the story couldn’t be told without them. They’re native to Arrakis, aka “Dune,” the planet where most of the book takes place. It’s a harsh desert planet where water is sacred, settlements are few, and traveling across the sand is dangerous. Arrakis is the only source of the Spice Melange — an ultra-expensive drug used to enhance humans’ intellectual and psychic powers — but mining it is extremely dangerous, thanks in no small part to these giant creatures.

That’s not all that Shai-Hulud have done, however. Villeneuve’s Dune may owe at least one of its 10 Oscar nominations to the giant sandworms, which visual effects supervisor Paul Lambert helped bring to life on the big screen. (Dune has been nominated in the Best Visual Effects category, in addition to receiving its expected Best Picture and Best Original Score nominations.) And if you’re a fan of Arrakis’ sandworms, don’t worry: There will be plenty more on-screen when Dune: Part Two arrives in 2023.

Here’s everything you need to know about the giant sandworms in Dune:

How Big Are The Sandworms, Really?

No one really knows how large sandworms can get, but they’re pretty big. Even the most average worm is capable of swallowing the 120-meter-long crawlers used to harvest the spice. Official reports from Arrakis indicate that they can grow to sizes longer than 400 meters (1,312 feet) and wider than 40 meters (131 feet), and Herbert’s novel features at least one sandworm more than 2,700 meters (8,858 feet) in length. For reference: A blue whale — the largest creature to ever live on Earth — only grows to around 30 meters, or just under 100 feet, at most.

Where Do The Sandworms Come From?

Arrakis doesn’t have much native flora or fauna, and yet these mind-bogglingly large worms live there in such numbers that they pose a real threat to humans. How? Well, it helps if you’re actually several native species bound into one.

The sandworms begin their lives as sand plankton, which feed on the spice found in Arrakis’ dunes. Eventually, the sand plankton grow into sandtrout, which burrow deep beneath the desert’s surface and locate its natural water reserves. A few of those sandtrout morph into small sandworms of a few meters in length, and a few of those sandworms eventually grow to become the giants for which Dune is known.

Oh, and a word about those giant sandworms: They can eat pretty much anything, but the sand plankton are one of their main sources of sustenance.

Why Are They Dangerous?

“Walk without rhythm” is an oft-repeated phrase in the Dune fandom, and for good reason. Sandworms are attracted to movement in the desert, and they can travel up to about 50 miles an hour to reach a moving target. In addition to walking in erratic patterns, Fremen and other desert travelers use thumpers — devices that beat a rhythm into the sand, which distract the worms — to protect themselves.

Why Do The Fremen Call Sandworms “Makers”?

Shai-Hulud isn’t the only name the Fremen have for the sandworms. They also call them Makers — in singular, the Maker — and religiously revere them for their connection to the spice.

Remember the sandtrout? The Fremen call them “Little Makers.” When their bodily fluids mix with water, the result is a pre-spice mass. Those masses give off fumes, which build under the pressure of the sand and eventually explode to the surface, where the pre-spice masses’ material is exposed to the hot, sunny atmosphere of Arrakis — and thereby turned into the Spice Melange. The process kills most of the sandtrout involved, leaving few who can further metamorphose into worms.

That’s not the sandworms’ only connection to the spice, however. They’re also crucial to the Water of Life ritual that turns Bene Gesserit Sisters into Reverend Mothers (either that, or kills them in the process). In order to harvest the Water of Life — a super-concentrated version of the spice — a sandworm must be drowned. (After the sandtrout stage, practically any amount of water is lethal to a Maker.) Drowning causes the sandworm to release a bit of spice-rich bile, which is then ingested by the potential Reverend Mother. If she survives the ordeal, she gains access to the Other Memory: a shared genetic memory network accessible to the Bene Gesserit.