Patrick Stewart as a neo-Nazi out to silence a punk rock band that could tie him to illegal activity in ‘Green Room’ (Photo: Scott Green/A24 via AP)

Warning: This story contains spoilers for a shocking scene in the new thriller, Green Room.

A baby alien bursting through Kane’s chest, showering the Nostromo crew with blood. Norris’s exposed gut transforming into a giant mouth and making a meal out of Dr. Copper’s hands. A possessed Regan twisting her neck until it makes a full 360-degree spin. Three all-time great nightmarish movie moments — from Alien, The Thing, and The Exorcist, respectively — relying on the art (and science) of practical effects, using makeup rather than computer-generated images. These classics set the bar for the specific kind of visceral jump scare that director Jeremy Saulnier hoped to deliver in his third feature, Green Room, a low-budget thriller that’s in theaters now. “Growing up, I loved films like John Carpenter’s The Thing and Paul Verhoeven’s RoboCop,” the filmmaker tells Yahoo Movies. “When a kid has access to a camcorder in 1984, they don’t want to make a chamber drama. They want to get in the backyard and blow stuff up!”

A siege film in the vein of Carpenter’s Assault on Precinct 13, Green Room doesn’t feature any fiery explosions, but it does boast one particular moment of intense tactile gore that would make his childhood mentors proud: a frenzied pit bull tackles and then tears out the throat of one of the musicians. And like virtually every other bit of gore in Saulnier’s blood-soaked movie, that gruesomely awesome moment is a practical effect, achieved through a combination of camera placement, makeup, and good old-fashioned puppetry. At a time when digital effects have become the industry standard even for independent genre pictures, the modestly budgeted Green Room makes a strong case for what the practical method still can achieve. “I love the tactile nature of makeup effects,” Saulnier says, simply. “It’s sculpting, it’s painting, it’s engineering. It’s pure movie magic.” Here’s how they made the mayhem.

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Saulnier had relied on practical effects for the more modest amounts of bloodshed in his previous film, Blue Ruin, which won rave reviews on the film festival circuit and in its subsequent 2014 theatrical release. But the premise of Green Room demanded more—and more complex—makeup work. Set largely in a dive bar nestled in the backwoods of Oregon that’s frequented by neo-Nazis, the film follows the attempts of a visiting punk rock band, The Ain’t Rights, to escape the place with their lives after one of the musicians stumbles upon a murder scene. The group barricades themselves in the backstage green room, but, to borrow a line from Game of Thrones, the bar is dark and full of terrors, terrors like rampaging pit bulls and gun-toting white supremacists unleashed upon the unprepared kids by the skinhead ringleader, Darcy (Patrick Stewart), who is taking no chances that the kids will go to the police. As the standoff plays out, casualties mount on both sides and the odds of any of our heroes surviving grow increasingly slim.

In tandem with his script, Saulnier developed detailed storyboards for Green Room that illustrated exactly how he hoped to realize his descriptions of mutilated arms, sliced-open stomachs, and lungs that become dinner for snarling dogs. He brought those drawings along with him when he met with Mike Marino, the owner of Prosthetic Renaissance, a special effects house that has previously designed Natalie Portman’s swan transformation in Black Swan, and Michael Keaton’s new nose in Birdman. “Jeremy was a fan of our work and reached out to us,” Marino says. “For this film, he really wanted to step up the makeup effects game. We liked the script, and his enthusiasm. He’s one of those directors who understands how practical effects work and how to use them.”

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