Halle Berry was really tethered in the woods for her horror film “Never Let Go”: 'There were bears out there!'

From cigarette burns to spider tattoos, the Oscar winner also talks crafting an elaborate backstory for her troubled matriarch in Alexandre Aja's psychological horror.

Halle Berry plays a troubled mother haunted by an evil in Alexandre Aja’s latest psychological horror film Never Let Go, but the most terrifying aspect of production? Definitely the bears.

“We were really in the woods in the middle of nowhere in a house that we found,” the Oscar winner tells Entertainment Weekly of the thriller’s live set. “That helped a lot because sometimes, if we shot in the daytime, with the way the lighting would come through, it felt magical, like you were in the most lush fairytale world.”

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But at night, “it became the scariest place because there were sounds we didn't recognize,” Berry says. “We didn't know what those animals were. There were bears out there! We had bear spray all around because you never knew when a bear would roll through our set, which happened many times.”

The terrifying nature of the environment, though, fueled the performances, Berry says. “We had to feel all of that to play these characters. We had to feel the wonder of the world, and we had to feel the fear of the world. The woods became a character in and of itself.”

In the film, Berry, also an executive producer, plays June, known simply as Mama to sons Samuel (Anthony B. Jenkins) and Nolan (Percy Daggs IV). For the past decade, they’ve been confined to a cabin in the remote woods after an entity Mama refers to as the Evil took over the world. When they forage the surrounding woods for food, they tether themselves to the cabin via rope as means of protection and promise to “never let go.”

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When the food runs low, Nolan begins to question if the Evil is real. And once the ties that bind are severed, a harrowing fight for survival ensues. “I love when I play a protective, strong mother role; that sits very well in my body,” Berry says. “But this was a chance to play a darker version of a strong mother. This mother had demons of her own that she was dealing with, generational trauma she was trying to work through while trying to be a protective mama bear. I thought that would be an interesting challenge.”

It was Holly Jeter, the other namesake half of Berry’s production company HalleHolly, who first stumbled upon the script and urged Berry to take on the role. “I couldn't put it down once I started reading,” Jeter tells EW over email. “During the scariest part of the script the power went out in my house. I was suddenly sitting completely in the dark. That had to be a sign!”

As producing partners, the duo gravitate towards “complicated, messy, three-dimensional characters, particularly women, who we don't necessarily need to like so much as we want to understand and follow on their journey,” Jeter says. “Halle has this incredible ability to play characters that may appear unsympathetic on the surface, but out of whom she is able to elicit a great deal of humanity.” Thus, “there was no doubt in my mind that this was her part to play, and I would not stop pushing until we made that a reality.”

In addition to poring over details of the family's appearance and mannerisms, Berry's prep involved crafting an elaborate backstory for June — one not explicitly defined on the screen. “Why does she have that snake tattoo? What do those spiders mean up her arm? What are those cigarette burns on her back? That will give you a little Easter egg of a life hard lived before she arrived at this house,” Berry says. “Something happened to Mama. The question is what, and that's for the audience to try to figure out. When you have cigarette burns on your body and spiders up your arm, you can only imagine what her world might've been like.”

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What really helped layer the performances, though, was the fact that Berry and her onscreen sons were actually tethered while filming. “Sometimes we were too far away from the house depending on the scene, so we had to get tied to a tree or piece of heavy equipment that would only allow us to go so far,” Berry says. “We always had the feeling of working against the resistance of the rope. It provided challenges sometimes to maneuver around with that, but that just fed to the reality of the situation.”

Berry praises Jenkins and Daggs as “more professional than some adult actors I've worked with,” crediting her young costars for helping her fully tap into June/Mama. “A big part of acting is connecting to that childlike part of who we are so that we can be free and unafraid,” she says. “We can take risks and be vulnerable. I love working with kids because they're all of that.  Life hasn't taught them yet that they need to guard their hearts. They're just who they are. I learned a lot from watching them.”

Never Let Go is in theaters Sept. 20.

Read the original article on Entertainment Weekly.