Shailene Woodley Feared a Theo James Knockout While Filming ‘Divergent’

The fighting sequences in "Divergent" are pretty hardcore — and often depict bloody, bare-fisted battles.

They're so intense, in fact, that leading lady Shailene Woodley, who plays Tris, admitted to Yahoo Movies that she was afraid at times during filming.

"That was terrifying — when I had to fight Theo [James]," she said, explaining that the 6'1" actor is an incredibly strong fighter.

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James plays Four, Tris's trainer, her love interest, and yes, in one key scene, her adversary.

"Homey's got some power behind those arms and we learned the choreography the morning of the scene," the 22-year-old Woodley recalled of her "Divergent" leading man.

The scene in question happens toward the end of the movie, when Four (James) is momentarily brainwashed. In a drone-like state, he fights Tris — who he has also kissed beforehand when fully conscious — at the behest of a villain-controlled machine.

"I was afraid if I ducked a certain way or if I forgot to block a certain punch he would have knocked me out cold," said Woodley. "Hands down, he would have taken me down."

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Miles Teller, who plays the mean-spirited Peter, also let us in on his fear landscape: "When we had to run on the train I was a bit nervous about that ... It was going pretty fast."

In the film, Peter gives Tris a bad beating in the boxing ring — a stark contrast to their love scene in "The Spectacular Now," in which they co-starred as a high school couple. "Fighting him was fun," Woodley said. But she also admitted to having some reservations. "[He's] sort of like my brother," she added, saying he can annoy her to the point where she wants to punch him. "But at the end of the day, the amount of love I have for [him] transcends the annoyance."

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Teller revealed that Woodley did get to nail him good, though. "That moment where she punches me in the throat — we had to do that a couple times because she was too scared to do it. Then when she actually did do it, yeah, it totally caught me off guard."

"Divergent" muscles its way into theaters on Friday.

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