The Old Guard: Inside Charlize Theron's transformation into an ax-wielding, millennia-old warrior

Charlize Theron is certainly no stranger to stunts, whether she’s taking down Cold War criminals in Atomic Blonde or careening across an apocalyptic desert in Mad Max: Fury Road. But her latest action outing, Netflix’s The Old Guard, required her to add new skills to her arsenal — like wielding a colossal two-handed battle-ax. “I had the most incredible shoulders after,” she says with a laugh.

Just to be able to lift and swing the heavy weapon took months of extra training to build up her strength. “I’ve never had to do anything like that,” Theron, 44, adds. “You have to learn to fight with that ginormous thing in a way where you don’t kill the person that you’re fighting with.”

Ax-wielding was just one of the many demanding stunts required for The Old Guard, Gina Prince-Bythewood’s action drama about a ragtag squad of undying mercenaries. Based on the comic series by Greg Rucka and Leandro Fernandez, the film (out July 10) follows this small team of immortals as they evolve and age (and age and age) through history, impervious to injury or illness. They’ve spent the last few centuries brushing up on their battle skills, and their millennia-old leader is Theron’s Andy, a.k.a. Andromache the Scythian, an ancient warrior who can be as deadly with a handgun as she is with her signature ax.

Unfortunately for Andy and her death-proof friends, avoiding detection is trickier in the 21st century than it was in the ninth, and soon the Old Guard are targeted by mysterious enemies who are eager to unlock the secrets of their immortality. The team finds an ally, however, in a freshly immortal U.S. Marine named Nile (If Beale Street Could Talk’s KiKi Layne). Nile is their first recruit in centuries, and she has to adapt to the challenges of eternal life (and the sad reality of watching her loved ones age).

“These types of films — especially action films of this size — usually follow a male character, and there are female characters, but they’re just kind of orbiting around whatever his story is,” Layne, 28, says. “This film [has] the ability to carry two very strong female stories.”

The newbie Niles finds a reluctant mentor in Andy, as the two women bond over the loneliness of immortality. “Most people can’t relate to slinging a giant sword around [and] really messing people up,” Layne cracks. “But people can relate to experiencing loss, or experiencing something that changed the trajectory of their life.”

“They are warriors,” adds Prince-Bythewood (Love & Basketball). “[I wanted] to be able to reframe what it means to be a female with this film and make that a normal thing: our toughness and badassness and courage. To normalize that was really important to me.”

To prepare to play elite mercenaries, Layne and Theron underwent months of training with fight coordinator Daniel Hernandez. As a Marine, Layne’s Nile can certainly hold her own in a fight, but Theron’s Andy is the expert, having picked up moves from around the world over the last few centuries. “We looked at all kinds of different styles — styles that came from the Middle East, styles that came from Mongolia,” explains stunt coordinator Brycen Counts. “I mean, just anything ancient we could come up with, and also new tactics as well.”

The two women’s fight styles are showcased in an early scene, where Nile and Andy go hand-to-hand in a rickety cargo plane. “That was the very first thing that we filmed,” Layne says. “That was day one. I was like, ‘Wow, just throw me into it!’”

Even an action expert like Theron calls it one of the most difficult projects she’s ever taken on — made even more challenging after she tore a tendon in her left thumb during the final weeks of filming. After wrapping, she needed three surgeries on her left arm.

“I definitely cried quite a bit,” she admits. “Everybody kept saying, ‘This is probably serious,’ and I was like, ‘We can’t talk about that right now. We just have to keep going because what are we going to do? We have three more weeks to shoot. We’ve got to get through it.”

Ultimately, however, Theron says she’s most proud of how hard she, Layne, and the entire stunt team worked to make every fight look as epic as possible.

“That was the thing that [Prince-Bythewood] really wanted: for everything for Andy to look effortless, like it’s almost a bore,” Counts says. “She’s seen everything, she’s killed everything, she’s been killed by everything.”

After all, centuries of practice should make perfect.

“A lot of my feedback from my trainers was always like, ‘You’re making it look too hard,’” Theron says with a laugh. “I was like, ‘Because this is really f—ing hard!’”

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