How 'Stranger Things' Built Its Terrifying Monster

Warning: This post spoils the last episode of the Netflix TV series Stranger Things.

Netflix's retro-spooky adventure series Stranger Things is a love letter to early 80s supernatural adventure movies—the blockbusters where the young protagonists wear corduroy pants and have pudding-bowl haircuts. But it also owes a great deal to Jaws. A movie about grown-ups on a boat might not be an obvious reference point for Stranger Things, which is steeped more in Steven Spielberg's kids-in-the-woods-with-flashlights oeuvre. But Spielberg's 1975 killer shark movie is probably the most famous cinematic example of the "wait as long as possible to show the monster" movie principle.

And the monster in Stranger Things definitely kept viewers waiting.

Over eight episodes, the show rolls out stranger and stranger things (see what I did there?) right up until the final installment, when, at long last, we're allowed to see the strangest thing of them all: the demogorgon, a.k.a. the creature, a.k.a. the monster. Once revealed, we've spent so much time dreading the monster's ability to harm our heroes that it barely has to wiggle one of the giant flower petals that make up its face to succeed in horrifying us. And it does more than wiggle its petals.

Veteran actor/performance artist/choreographer Mark Steger, who occupied the monster suit, was kind enough to grant us an interview, so we could find out what went into the creation of his character. It turns out there's more of a connection to Jaws than just the timing of the creature's reveal—or, as Steger suggested, her reveal.

VICE: What's with the petals? Is the monster a plant monster?
Mark Steger: That's a fair speculation. I feel like the monster maybe is more mushroom, which is kind of between plant and animal. Mushroom DNA is more similar to animal DNA than to plant DNA, [but the monster is] something else. He bleeds—or maybe they bleed, or she bleeds. I don't know what pronoun to use for the monster! But it feels like a little bit of both [plant and animal] to me.

At moments where we just barely see the monster early in the show, is that you?
I'm wearing the full costume. There were times when I would take the stilts off for more mobility. When you're in the woods, there are branches and rocks and things, so you can be a little unstable. But that's me in the full regalia.

Did you have to go through one of those crazy, all-day makeup processes?
The process of [putting] it on actually wasn't too bad. It took about a half hour or 40 minutes total, depending on whether or not we were using the full animatronics, [and] the animatronic head, or the stunt head, which was just closed all the time. I was raised up about eight or ten inches on these metal stilts. It was partly puppeted, and there were a lot of animatronics. And servo motors and batteries. It was pretty complicated.

I've read that the monster was mostly done without computer graphics. What's computer generated?
There are some digital enhancements. When the head opens, my eyes were there, so they replaced that digitally with an animatronic mouth that was built by [Los Angeles creature-effects house] Spectral Motion.

In that case, we're only able to see when the petals opened?
Yeah, I could see better when they opened. When they were closed, there were a couple little gaps, but they weren't always in the same spot.

Were the hands computer-generated? It seems like your arms would have to be super long for those to be your real hands.
The hands were animatronic. I was puppeting the arms. My arms were covered in digital green sleeves that were removed in post. It was like I was part puppet. I was part machine. I was part human, animating the whole thing. It was a very complicated process.

Was working without being able to see the biggest challenge?
It was actually really loud in there. Even when the motors were turned off, there was this high-pitched whine. And there were 26 motors running the head, and when we were actually doing a shot, I couldn't hear directions. They would have to shout at the top of their lungs, and then maybe I would hear them. The suit probably weighed about 30 pounds or so, and you're completely sealed in. It's like wearing a wetsuit and covering your whole body.

Sounds hard. Did you ever break down from sheer effort?
Having really good endurance is a really important part of this job. I usually nibble on potato chips all day and drink electrolytes of some sort just to keep going. You can't eat a heavy meal and get in the suit. For one thing, the suit's tighter. But also you also have to regulate your blood sugar when you're in there. I'm really thin, so I burn calories really quickly, so I'm always having to manage that.

What was the hardest part?
The whole scene where I was fighting the kids in the house: The actors Joe [Keery], Charlie [Heaton], and Natalia [Dyer] are there, I appear in the room, I'm shot, I'm beaten with a bat with spikes on it, I step in a bear trap, and I'm lit on fire. There was also the choreography of the fight. Of course, we shot it in pieces, but there were some parts where we did almost the whole thing. That was probably the most challenging one.

What does acting involve when you have all that technical stuff to worry about?
I was literally corseted into to the suit, trying to animate it so there was a little bit of exaggeration going on. And all the time, there are these kids you're battling with, who are trying to kill you, and you're trying to eat them. The conditions that are created by you getting into the suit really help you get in the mindset of being this other creature.

The moment when it ate the deer was probably the closest thing to seeing the creature just living its normal life. How'd you create that moment?
The animatronics designer, Mark Setrakian, was working with me most of the time, [and] I was kind of acting with him and cuing off him. He'd be undulating the petals, and I'd kind of rear back like I was taking a bite, and he'd open [the petals] and close them again as I brought my head down. It was an interesting interactive process. I spent a lot of time just waiting outside for some of those shots. You're very cold and a little stiff, and you're having to hit marks and inhabit the character.

What did the directors tell you in terms of the character's motivation?
The simple directions the Duffers gave me were, "You're basically a shark, like the shark from Jaws, and you travel between realms to feed." So that was my main goal in this character.

And what's your process for bringing that across onscreen?
I was just thinking, I'm like a shark. I am perfect for what I am built for. A shark hasn't evolved in 200 million years—or however long its been. So that's what I was thinking: This is what I do. I'm the best at it. I'm better than anyone else at it. It was great direction. They were very clear about what they were going for, which was very refreshing. They communicated well, and it was a fun process. What we're doing is a lot of work, and obviously it's very stressful, but it felt like play.

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