The fourth season of "Stranger Things" has plenty of highlights, but no episode stands out quite as much as "Dear Billy." The fourth chapter of the season has already become a massive part of the pop cultural zeitgeist since its May debut, thanks largely to a scene in which Max (Sadie Sink) faces off against the villainous Vecna (Jamie Campbell Bower) with the help of a classic Kate Bush song. But the episode also features one of the most impressive sequences the series has pulled off to date. It's an immersive one-take shot that apparently felt very real to the actors who filmed it.

In an interview with MTV News, series stars Millie Bobby Brown and Noah Schnapp discussed the scary scenes that "got to them" the most. For Schnapp, who plays artistic teen Will Byers in the show, there was a clear standout: the Lenora shootout. The sequence comes mid-way through episode four, when a conversation between Will, Jonathan (Charlie Heaton), and Mike (Finn Wolfhard) is interrupted by the sudden appearance of armed military men.

In a nearly 60-second Steadicam shot, the teens make their way through the house with the help of Agent Harmon (Ira Amyx), all while glass shatters and bullets whizz through the air around them. The house's retro, semi-open floor plan means the characters have plenty of places to duck for cover, and the camera is able to move kinetically through the action with them.

A Loud, Fast One-Take

According to Schnapp, the big action sequence felt stunningly real on set thanks to the practical effects that were employed during filming. "We were running through the house, and the whole day we rehearsed the scene without the bullets [blanks] or any of the action of it," Schnapp explained. "So on the first take they did it was with all the bullets and all the glass breaking and the whole house breaking down. Right on the first take I felt that raw fear."

Heaton clarified in an interview with GQ that the production used water round loads, which he describes as "like blank bullets, but they're loud." Brown also described the overwhelming nature of the scene setup, saying, "there's so many special effects and there's air and there's noises," all adding to the atmosphere and pressure to get it perfect. He commended the show's "amazing safety team" for making sure the scene felt safe, even if the commotion and chaos made it possible for actors to access real heightened emotions like the kind Schnapp described.

"For an actor at least, it makes it feel so much more real. It was really intense," Heaton said of the production setup, before singling out his costar's genuinely freaked-out facial expressions. "Noah is incredible," he said. "The faces that he has in this whole sequence I think was him genuinely being terrified. Safely terrified." Heaton also described the exhilarating and high-stakes shooting process for the scene, which involved filming the shot with several performers, stunts, and camera movements that needed to align, playing back footage on the monitors upstairs to look for imperfections, and tidying up the aftermath to do it all over again.

How They Pulled Off The Shootout

Episode director Shawn Levy, who manned the monitors that Heaton says everyone flocked to between takes, explained the unique obstacles of shooting a long take in a Netflix Geeked Week featurette. "The whole challenge with the oner is it requires perfect synchronicity between actor action, stunt action, and camera action," he said. "So every pan, every tilt, every move of the actor, it needs to be in unison." If one thing goes wrong in a dialogue scene, it's easy to have actors simply return to their marks and start over. If one thing were to wrong in a scene like this one, dozens of elements would have to be reset, including some that were apparently in limited supply. "It was all about how much breakable glass they had," Heaton told GQ, explaining that the team only had seven or eight chances to get it right. In the end, the actor says they nailed the sequence around their fifth attempt, after having to pause filming for some Albuquerque lightning storms.

Though Schnapp described the frightening sound of the blanks zooming past him when the first take started, it sounds like the Lenora action sequence ended up being a high-octane bonding experience for everyone involved. Brown says the cast piled into a group hug after learning they'd finally nailed the take, while Heaton describes the crew screaming in celebration. "It was definitely scary but it looks great," Schnapp recalled. Levy is proud of it too: in the behind-the-scenes interview, he called the oner "both the most challenging piece of directing and, ultimately, one of the most gratifying pieces of directing" he's ever accomplished.

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