'Hanna' Star Saoirse Ronan Recalls Her 'Rigorous' Training

'I'm a bit of a perfectionist, I guess, so I pushed myself quite a bit,' she tells MTV News.

She's a 16-year-old actress best known for starring in period pieces and surrealist trips through the afterlife. He's the man who brought Prince Hector of "Troy" and the menacing superhero Hulk to life. Which one would you bet on in a fight?

Let's just say that, despite all appearances, Saoirse Ronan is not down for the count. For her latest film, the high-octane coming-of-age action fairy tale "Hanna," Ronan put herself through a brutal two months of training to become a believable teenage assassin.

"It was rigorous, but it was great," Ronan told MTV News of her training process. "I trained for about two months before we started shooting, and I learnt new skills like knife fighting, stick fighting, how to shoot a gun, martial arts. There was a style designed by Jeff Amada, who's the stunt coordinator, and it was created specifically for the character of Hanna. It was based on the strength and energy and body type and things like that. We worked on that every single day, and I felt like I was starting to walk differently. I'd hold myself differently. I felt stronger, just after a few weeks. It was amazing. It was a great way to focus."

All those skills and more were invaluable for her portrayal of Hanna, a 14-year-old girl raised in a remote snow-covered forest in Europe with only Erik (Eric Bana), her father figure and cruel mentor, for company. Erik's methods are brutal, yes, but they're not without cause: He's training Hanna in the art of the assassin so she may one day venture off into the world and seek vengeance upon Marissa Wiegler (Cate Blanchett), the woman who ruined both their lives.

"I didn't think I couldn't do it, but I wanted to do my best," Ronan said of tackling such an action-heavy role. "I'm a bit of a perfectionist, I guess, so I pushed myself quite a bit. I had a personal trainer to push me quite a bit as well. It was probably the most preparation I've ever done for a film, definitely the most physical preparation."

That preparation paid off in spades for Ronan's action scenes, particularly against co-star Eric Bana. There's one scene early on in the movie where the two companions spar on a snowfield without holding anything back — but as Ronan tells it, it was only Bana who pulled his punches.

"I think he held back a little bit, because he was fighting a little girl," she said. "But I had a little voice in my ear — maybe it was Joe Wright, I don't know — and he said, 'Just go for it! Just do it!' So I went for it. You just gotta do it."

And don't expect her to feel guilty about it, either. "It was good fun, kicking the Hulk's ass!" she laughed.

"Hanna" arrived in theaters nationwide Friday (April 8).

Check out everything we've got on "Hanna."

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