Taron Egerton and Charlize Theron did most of their own stunts in Netflix's 'APEX.'

Photo by Kane Skennar/Netflix

In Netflix’s APEX, Charlize Theron plays Sasha, an adventurer who comes face-to-face with psychopathic serial killer Ben (Taron Egerton) deep in the unforgiving Australian wilderness.

Directed by Baltasar Kormákur and written by Jeremy Robbins, the 95-minute psychological thriller delivers an intense, unrelenting ride as Sasha fights to survive both the brutal terrain and a relentless killer in the middle of nowhere.

Ahead of the film’s April 24 premiere, Kormákur confirmed in an interview that both Theron and Egerton were determined to perform many of their own stunts despite the risks, something he admitted made him uneasy at times.

“There's so much that they did themselves, all the way to where I almost pulled back because I didn’t want to put them in any physical danger,” said Kormákur.

That concern isn’t unfounded. In press interviews, Theron revealed she has undergone surgery after nearly every film. One injury in particular stands out: while filming Æon Flux, she herniated a disc in her neck after landing on concrete. This accident nearly paralyzed her and forced a production shutdown.

After APEX wrapped, Theron underwent elbow surgery, followed by a revision procedure, and also dealt with a fractured toe.

APEX opens with Sasha and her boyfriend Tommy (Eric Bana) scaling Norway’s Troll Wall, setting the tone for the physical demands to come. Months later, a grief-stricken Sasha travels to the fictional Wandarra National Park in Australia, filmed in Australia’s Blue Mountains National Park.

There, she learns that numerous people have gone missing. While the disappearances are initially blamed on the harsh environment, Sasha soon realizes something far more sinister is lurking in the wilderness.

In an era where audiences often assume high-risk scenes rely heavily on green screens and AI, APEX stands apart. According to Kormákur, Theron and Egerton were eager to perform much of the action themselves, often pushing the limits of safety.

Some locations proved so challenging to access that, during scouting, Kormákur said they actually had to swim to reach them. One example he pointed to was the Grand Canyon in the Blue Mountains region.

Theron’s role demanded intense physicality, including whitewater kayaking and near-vertical rock climbing. Kormákur said she was determined to take on as much of it as possible.

“All of the challenging climbing, more or less, she’s doing it. A lot of the water work she's doing, too, especially swimming. She was thrown around a lot. With some of the kayak work, we did need some help there because that's a very difficult thing to master.”

Part of what makes APEX so unsettling is its plausibility, the idea that someone like Ben could exist in such isolation. Egerton’s portrayal of the feral antagonist stands out, shaped through close collaboration with Kormákur, who gave him leeway to go beyond what was on the page.

“When we met, it was all about, like, ‘Okay, are you willing to portray your inner creep? Are you willing to show people behind the curtain? To show your insecurities?’ We built the character from the inside out. I love the idea that he hadn't shown those cards that much in previous performances. It was something new, and I think from there, it just all became about finding the character.”

Kormákur emphasized a flexible, organic approach to the performance. “I was like, let the truth come out as you’re performing it, and find it there rather than deciding too much before we do it.”

He also referenced filmmaker Ingmar Bergman’s philosophy: “Only someone who is well prepared has the opportunity to improvise."

Kormákur embraced that mindset. “I let it all go when I'm on set. You can come prepared, but you have to be ready to allow what is performed to come through on the day.”

At its core, APEX is as much about grief as it is about survival. Sasha is coping with the loss of Tommy, whose ashes she has come to scatter after a tragic climbing accident. Kormákur sees her journey as deeply psychological.

“For me, the whole movie is like a purgatory for her because she blames herself and is dealing with grief and guilt. It’s a bad mix, and she’s punishing herself,” he explained.

As Sasha is forced into a fight for survival and ultimately to stop Ben, her arc becomes one of reckoning and redemption. “I thought it was very important to feel that in the end, that she actually comes through, and steps out of it, and manages to stop him.”

Sasha’s guilt stems from a devastating moment during their final climb. Tommy falls and is left hanging, pulling her down with him. Faced with an impossible choice, she cuts him loose to save herself, uncertain whether he was already dead or still alive. It’s a haunting decision that shapes everything that follows.

While Kormákur supported the actors’ commitment to realism, he even admitted that some scenes pushed his comfort zone. “If the actor wants to do it, I'm all for it. Of course, I want to have it safe. I don’t want to put anyone’s life in danger.”

One particularly intense sequence involves Sasha climbing straight up a sheer rock face, something Theron insisted on doing herself.

Kormákur admitted he was concerned. “That final ascent was more than I would have liked to do myself, you know?”

The scene was filmed on a real, jagged cliff, not a green screen, and required immense physical endurance.

“There were some security measures, but at the same time, just to go off that cliff and do that climb, it was incredible. Your knees would be shaking just standing there. That was one of the most intense moments.”

That sequence alone took an entire day to film, and it was grueling.

“She was just hanging off that cliff for a whole day,” Kormákur added, noting that Theron handled many of the climbs throughout production. Interestingly, he added that she found climbing easier than kayaking.

“For her, the climbing was much easier than the kayaking because that’s something she felt more in control of. She kept getting thrown by the water, so I think physically that was very punishing for her when she was doing some of the kayaking stuff.”

Egerton faced his own physical and psychological challenge in a scene that required him to dive from a very high cliff into the churning water below, and he did so multiple times.

“It was about 10 meters (32 feet) high, and he did that eight times, I think,” confirmed Kormákur. “He wanted to do it and push himself because he’s scared of heights. He was very clear about that. But he did it, and the fear in his eyes is real. It's not acting.”

In the end, APEX deserves to go down as one of the most intense thrillers of all time. It isn't just gripping because of its brutal stunts or breathtaking locations. It’s the raw authenticity behind every moment that lingers long after the credits roll.

When actors willingly step to the edge, physically and emotionally, that danger translates to the screen in a way no visual effect can replicate. The result is a thriller that doesn’t just entertain; it unsettles, immerses, and refuses to let go long after the final frame.