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Before production on Stranger Things 2 began, visual-effects producers Paul and Christina Graff had to figure out how exactly to turn the Duffer Brothers’ ideas into reality. Specifically, the Graffs needed a way to capture Will’s visions of a nightmare version of Hawkins subsumed by the Upside Down; the life cycle of Dart, the slug-like creature that Dustin adopts; and how to design the Shadow Monster, the season’s tarantula-meets-tornado Big Bad. Then, as shooting progressed, the Graffs had to solve problems on the fly to help plot out VFX shots, and also come up with workarounds for shots that you might not expect would need visual effects — like Eleven’s buzz cut. Vulture caught up with the Graffs over the phone to get the stories behind some of the season’s biggest, hardest, and otherwise surprising visual effects.

The Upside Down

In the first season, the scenes involving the Upside Down — the mysterious evil dimension connected to Hawkins Lab’s experiments with Eleven — were done practically. In this season, as Will Byers sees visions of the Upside Down taking over the town, the VFX team realized they would have to use digital effects to transform real settings into the alternate dimension. They accomplished that by scanning the sets and reconstructing them with 3-D models, within which they re-created the camera’s movements. “We’re looking at it like a parallel universe basically,” Paul Graff said. “You have these two parallel worlds and then you can put things into the CG world and it’s just going to line up with the parallel world.”

The spores

A key part of the Upside Down is the spores that float through it, making it look like a sinister version of the planet in Avatar. Those are also mostly CGI. “The Duffers are really picky about the spores,” Paul Graff said. “We tried to get practical spores, but they’d only work under special circumstances, so sometimes you could get the practical spores to work and sometimes you couldn’t. The kids weren’t super excited about spending a whole day with all of these flakes flying around, so I would say 90 percent of the spores you see in the show are digital spores. Maybe even 98 percent.”

The evolution of Dart

Dustin’s reptilian pet begins its life as the cute, slug-like creature Will coughs up at the end of season one, but it soon grows into a much less cute Demogorgon. “The Duffers wanted to show the evolution of Dart from a tadpole-like state with just a tail and two extremities to dog-sized, what we call a Dogogorgon or the Duffers call the Demodog,” Paul Graff said, explaining that the brothers came to them before the season began with Dart’s life cycle plotted out.

The Graffs worked with effects vendors ASC and Hydraulx in order to develop the various stages of Dart’s life, designing the creature’s interior organ systems alongside its exterior, as it’s semitransparent for much of its life. The goal was to only hint at its Demogorgon-like qualities in the tadpole and pollywog-sized stages before the kids realize the creature is sinister later on, as it becomes cat- and then dog-sized. “It’s this cute and curious odd little creature for the first two stages,” Christina Graff said. “Only in stage three do we realize it’s actually a Demogorgon.”

The Shadow Monster

“We knew from the Duffers that it would be humongous, like 50 stories tall,” Christina Graff said of the monster that looms in Will’s visions. “Since we had all these electrical disturbances last year in season one, where the Christmas lights were blinking or any sort of electrical light is blinking, we knew there were going to be storms in season two. The Shadow Monster is somehow connected to all of that energy, and then we determined it’s gonna be like cloud-like or storm-like. We had conversations also with the production designer, Chris Trujillo, and we searched for a lot of references to storms and clouds and things like tornadoes.”

The Graffs also talked with Steve Messing, a matte painter who had consulted on Dart’s design as well as other Stranger Things elements, to help make concept drawings based on tornadoes, volcanoes, and other natural forces, which Trujillo had researched. “Chris found these volcanic eruptions with lightning storms somewhere in South America, where you have this kind of ashy cloud with a lightning strike that comes out of the cloud and hits right back into the cloud. So that looked really cool,” Paul Graff said. “We figured we need a storm with orange lightning and a 50-story-tall monster that doesn’t look like a spider. The Duffers didn’t want it to look like a spider. “

One of the Shadow Monster’s most distinctive attributes is the way it attacks Will, with a spindly, tornado-like appendage that infects him. In the season’s fourth episode, the camera circles Will as Joyce attempts to reach him, cutting between the real world and the Upside Down. As Paul Graff explained, “We knew we needed a green screen, but we have to walk around with the camera in a circle and we need the green screen always on the other side. That’s a technical problem.” The solution was a tricky one: They rigged up a circular rail with multiple cameras — “one camera dolly had the camera, obviously, and a reference camera to shoot the ground so we know at all times where we actually are in space” — to get the correct shot. “We ran this choo choo train around Will and in the camera, there was a green screen, but there was also 20 or 30 percent of the train where you could see the actual background,” Paul Graff said. That way, the team could insert the monster between Will and the background while keeping consistency with the moments from Joyce’s perspective. “It was pretty cool,” he said.

Kali’s illusions

In the stand-alone seventh episode, Eleven ventures out of Hawkins to find Kali, another test subject who can conjure illusions in the minds of people around her. “She needs to work with strong images and impressive images because they can’t be probed — they’re not really physical,” Paul Graff explained. So when Kali summons a wall to protect Eleven and her friends, for instance, the team knew they needed something impressive. When she summons a butterfly, they also knew that they wanted something distinctive, though the Duffers weren’t always sold on making it bioluminescent. “We had a weight on a fishing rod that was there, so [the actors would] know where to look,” Paul Graff said. “Then we erased that digitally, put a butterfly in, and we gave the bioluminescent butterfly one more shot and the Duffers loved it.”

The final showdown

Eleven’s battle with the Shadow Monster in the season finale was shot on a soundstage, so that the visual-effects team could add the massive portal-like rift that divides Hawkins from the Upside Down. “We knew that the rift cavern was gonna be something like 150-feet, 200-feet tall and, I don’t know, 70-feet diameter,” Paul Graff said. “The only thing that we built was the half of the bottom. Everything else is pretty much a full CG environment.” In order to make that environment look seamless, the Stranger Things team spent a lot of time plotting out lighting design that would match the battle. As the monster becomes more aggravated, the rift glows bright, while Eleven also shoots white light toward the monster. In what the team nicknamed the “Mother Mary shot,” we see Eleven from behind with the monster’s tendrils mushrooming toward her. “The lighting changes between it being the red glow that becomes more intense as she aggravates [the rift] to the white light of it actually closing,” Paul Graff said.

… and of course, Eleven’s buzz cut

When we first see Eleven in the early episodes, she’s started to grow out her distinctive buzz cut into a curly, short head of hair. But Stranger Things 2 needed flashbacks to fill in what happened before the season began, the production team realized they needed to re-create Millie Bobby Brown’s old haircut. “Nobody felt like it was a good idea to cut her hair again,” Paul Graff said, especially since Eleven’s hair would need to continue to grow out for the next season. “We experimented with the wig and the wig added too much volume to her hair, because you have to get her hair and then you have to have base and then a cap and then the wig. Everybody felt that it was better to just go full digital with the hair.”

“In the end, we had to re-create her look, the same hair that she had in season one,” Christina Graff said. “We basically tracked new hair onto her head for all of those scenes.”

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