The actress, 41, took on her role as MI6 agent Lorraine Broughton in full, training for two to three hours a day in all kinds of martial arts for six weeks before filming even started.
“The entire stunt team was very pleasantly surprised at her overall physical ability,” stunt coordinator Sam Hargrave tells PEOPLE. “She was extremely tough; she did 95 percent of all of her own fighting.”
Theron was so good that they completely changed their filming plans. At first, Hargrave and director David Leitch expected to film her throwing a punch or two before yelling cut and resetting the scene.
“But she showed that she could do 10, 15, 20, 30 moves in succession without needing to cut or reset,” Hargrave says. “We were like, wow, this is special. This is unique. We need to take advantage of this.”
Hargrave chalks most of Theron’s abilities up to her intense dedication.
“A lot of it is natural, God-given talent that she was born with. She’s just a very coordinated and athletic person to begin with, but I can attest to the hard work that she put in, and that’s what separates the good ones from the great ones, in my opinion,” he says. “Hard work was one of the bedrocks of her training, and I think it really shows in the final product.”
And the stunt crew was similarly impressed.
“She would do sacrifice throws, she was rolling around on the ground. The stunt crew — they all loved her, and how she gave as good as she got. They were trading throws,” Hargrave says. “She would push the stunt guys to a level that she knew she could take or beyond.”
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Theron was also very careful about what she ate. “During training she was very strict with her diet, very strict with her training regimen, and she was trying to stay lean and fighting fit because she had so much action,” Hargrave says. “And she had a lot of scenes where she was wearing very little so she wanted to be in the best shape possible and she trained very hard for that.”
Hargrave says Theron’s impressive fight work brought a realism to the role of Lorraine, and could inspire a new feminist icon.
“The film is kind of statement on feminism. We saw her, Lorraine Broughton, in a great embodiment of that in Charlize Theron as a strong, able-bodied woman who is just as tough, if not tougher, and just as strong, if not stronger, as a man in that role,” Hargrave says. “So it’s not about male or female — it’s about the humanity of that. It’s about bringing a reality-based portrayal about the humanity of that in those situations.”