Fifteen minutes after Josh Brolin met 13-year-old Hailee Steinfeld for the first time, he was pinning her down with a blade to her throat.

No, this was not another shocking case of When Celebrities Attack. Brolin and Steinfeld were on the set of Joel and Ethan Coen’s True Grit remake, opening today, and their introduction preceded the rehearsal of one of the movie’s tensest scenes.

Steinfeld, playing Mattie Ross, the precocious, fiercely determined heroine of Grit, seemed unfazed by the prospect of grappling with the bearlike Brolin. She approached the scene with the same uncanny poise she brought to the rest of her time on set.

“I think it was more nerve-racking for me than it was for her,” says Brolin, 42. “She’s very comfortable in her own skin. That scene was about her talking and being super-confident and this man-child hating her purity.

“You know, everything she did was easy. The rest of us searched a lot in rehearsal for character and all that, but she already had it. She was the one person who had it down before the rest of us really started.”

Despite her age and relative inexperience – she made her TV debut in 2007 on the FOX series Back to You, and has since appeared in just a few shows and short films – Steinfeld easily held her own in scenes opposite co-stars Jeff Bridges, Matt Damon and Barry Pepper. Did she ever feel intimidated by all the testosterone?

“It wasn’t bad,” says Steinfeld, a Thousand Oaks native whose father took her to a shooting range with a Los Angeles cop so she could learn to fire a gun for the role. “I was surrounded by women the entire time – the hair, makeup and wardrobe people. My mom was with me, so was my tutor. But I feel like all [those guys] are like big kids, so it was a lot of fun.”

Steinfeld’s greatest challenge, besides learning to roll cigarettes and performing most of her own stunts, involved mastering the film’s baroque Old West dialect and finding some emotional value in it. That it didn’t take long came as no surprise to the Coens.

“Ninety-nine-point-nine percent of the hundreds of girls who read for this part washed out at the level of not being able to do the language,” says Ethan. “Right from the beginning it was clear that Hailee was completely comfortable. She had it from the get-go in a very, very natural way.”