Nightmare on Elm Street's Robert Englund Recalls Making Costar Heather Langenkamp 'Jump' with Freddy's Claw on Set (Exclusive)

Ahead of the 40th anniversary of A Nightmare on Elm Street, which first debuted in theaters on Nov. 9, 1984, stars Robert Englund and Heather Langenkamp are looking back on the making of the now-iconic slasher film, which went on to launch a whole horror franchise around the sadistic child killer Freddy Krueger.  

While the character created by the film's writer and director, Wes Craven, is a horror icon all on his own, Englund, 77, has revealed to PEOPLE that a lot of trial and error went into the final figure seen on-screen, from all the makeup tests to get Krueger's burned skin to look just right to panic over what kind of hat he should wear. (Luckily for all, the production settled on the fedora over a Newsies-like paperboy hat.)

Admittedly, it even took Englund time to find Krueger's voice, which almost happened by accident when snarled at the special effects artist during one of his many days in the makeup chair. 

But as Englund tells PEOPLE, he knew he found Krueger the moment he saw his silhouette in a mirror. "I remember one of those was tacked up and then seeing [myself] and getting the idea," he shares while promoting Nightmare's 4K Ultra High Definition (UHD) release. "Because of the overhead lighting, once I had that hat on and the glove, I saw the shadow. I saw the Freddy silhouette in the shadow and I went, 'Aha, this is something I can work with. This is something I can exploit.' "

And once the production landed on Krueger's look, it was time to test just how scary he would be on set. For Langenkamp, 60, it was a frightening introduction to the undead killer that would end up stalking her character, schooler Nancy Thompson, and her fellow high school classmates while they slept. 

"I hadn't seen Robert in makeup for several days and I went into the [high school] scene where Tina [Amanda Wyss] leads me down into the boiler room and I got down there and I saw Freddy for the first time," the actress says. 

At that moment, Englund was in character, wearing "the shadow with the hat, the sweater, the boots and the glove," and Langenkamp says, "It was really striking and I knew at the moment he was terrifying. I never had to act that part because he was always terrifying to me."

Not only that, but Englund remembers giving his costar, who was just 20 at the time, a jump on set. While filming the scene opposite Langenkamp, he remembers Craven trying to get the actor to hold up his claw glove high enough so it appeared on camera. 

"Wes needed to see the claw in the shot. He was cutting it, you know, mid-waist I think," Englund recalls, explaining he was having issues with "just hold[ing] it there" because it felt unnatural. "I've had that same problem with directors who wanted me to get a gun in the show. When you're pointing a gun at somebody, you know, it looks cool right here," he continues, demonstrating the motion by lowering his arm to around his stomach area, whereas to get it in the frame, he had to hold it higher, closer to his chest. "But a gun up here looks silly. So I didn't want to hold the claw up here." 

He continues, "So I remember I scratched it on a pipe. And Heather jumped a big. I mean it really worked." That's when Langenkamp jumps in to say, "Plus it made that sound." 

"Like nails on a chalkboard," Englund clarifies, adding, "She moved a little extra and I thought, 'This is something we can work with as well.' "

Adding to the terror Langenkamp felt on set was the glove itself. While the character has metal claws coming out of his leather accessory, the actress says the one Englund wore was a prop. "The glove had rubber blades," she says, noting that even though they were fake, "the rubber blade goes in your eye, it's still gonna hurt, right? So, yeah, I was constantly really worried."

"We're working in the dark a lot and so you could understand why she would be unnerved by a guy walking around with razors on his fingertips," Englund quips. 

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Speaking to the nightmarish horror that Craven's team brought to life for the film, Langenkamp told PEOPLE earlier this summer the moment she realized what kind of terror Krueger would be to audiences watching Nightmare on-screen.

"There were also the scenes in the alleyway, where Freddy says his famous 'This is God' line, and I remember being there, realizing how frightening that particular line would be for so many people," she said of the moment when Tina (Amanda Wyss) was sent fleeing for her life.

In honor of its 40th anniversary, Warner Bros. is releasing A Nightmare on Elm Street on 4K UHD digitally on Oct. 1 and on physical on Oct. 15.