You're never too young to start conserving, and Saoirse Ronan, who turns 17 on April 12, puts that into practice. "I do something that everyone should do: turn off the water when you're brushing your teeth. You don't need the water on. And I always turn off lights when I'm not in the room, and take plugs out of sockets. There are a lot of things that people can do that will help," says the Irish actress, who hopes to get a fuel-economical MINI Cooper for her first car.

 

Ronan teamed up with her "Atonement" director Joe Wright to play the title role in "Hanna," a spy thriller opening April 8. She plays a teenager who grew up in the wilderness with an ex-CIA agent father (Eric Bana) that taught her to be an assassin in preparation for fighting back against the people who'd like to kill her. "I like the fact that she's not a typical action heroine. She's badass and clever and she's strong but she's very reserved," Ronan begins. "She has a simple outlook on life. She's not prejudiced. She doesn't really make a judgment on anything. She's very pure, naïve and innocent but suddenly with one switch she's a killer."

 

Ronan trained for two months before shooting began in such far-flung locales as London, Finland, Morocco and several places in Germany and worked with stunt coordinator Jeff Imada to get the fight choreography down. "I learned martial arts. I did weapons training. I learned to work with sticks," says Ronan, who didn't find the action sequences particularly difficult. "I've always been quite an active person so I guess I had a bit of a base there already." With the exception of one jump from a particularly high cargo container, "I did all my own stunts," she reports. The toughest part, she says, was shooting in Finland "because of the cold. It was like minus 30 degrees."

 

Home-schooled and tutored when she's on set, Ronan would like to go to college. "I wouldn't study acting. I already do that. I'd study something artistic like art history or literature," she says, but right now her acting career is keeping her very busy. She'll star opposite Alexis Bledel and James Gandolfini in the black comedy "Violet & Daisy," and is tentatively set to re-team with Peter Jackson, who directed her in "The Lovely Bones," in "The Hobbit," playing an elf named Itaril. She'd welcome a chance to return to New Zealand to film it. "It's amazing, and it would be great to work with Pete and his crew again," says Ronan, whose wish list includes making a film a bit closer to home. "I'd like to work on a film in Ireland, with an Irish director and crew, and play an Irish character so I can use my own accent."

 

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