But the Canadian actress has returned to her romantic roots with new drama "The Vow," due in theaters on Friday. The actress portrays Paige, a young bohemian artist happily married to Leo (Channing Tatum) until a devastating car crash leaves her with a head trauma that erases her entire memory of their relationship.

While Leo tries in vain to get her to remember him, Paige reverts back to the person she was five years earlier -- a law student with a conservative wardrobe who doesn't understand why she's estranged from her parents or why she broke off her engagement to a charming businessman (Scott Speedman). Leo must make Paige fall back in love with him if he is to win her back.

McAdams, 33, sat down with Reuters to talk about the film, the surprise success of Oscar-nominated "Midnight in Paris" and why she feels compelled to always take breaks between projects.

Q: "The Vow" is actually based on a real story that happened to a couple from New Mexico. Did you meet Krickitt Carpenter, the woman upon whom the character Paige is based?

A: "I did. Both Channing and I met her and her husband (Kim Carpenter). It was nerve wracking at first because you want to do justice to their story. At the same time, our story was only inspired by them, so we were playing different people. But they are an incredible couple. They had a strong faith in God and had that to fall back on. They had only been married two months when it happened in the early '90s. Today they have two children."

Q: Your character dressed and behaved one way before the accident and another after it. Was that challenging?

A: "It was difficult to play almost two different people at times, and to keep the thread going between my character and Channing's character. You want some sense of hope that these people might find each other again. I did some research into brain injuries and the emotional effects of that. It's quite isolating. The more your family and friends try to bring back your memories, the more you pull away."

Q: Your other film out there, "Midnight in Paris," is nominated for four Academy Awards, including best directing and writing for Woody Allen. Are you surprised at its success?

A: "You never know how these things will go. Reading the script, I loved the sentiment. I loved this idea of Golden Age thinking and that maybe we should just celebrate the time we're in rather than wishing we were somewhere else. Woody continues to communicate truths about life in such a funny and wonderful way that not all of us can articulate. I love that people responded to this film."

Q: Yet the most magical parts of it -- the period parts set in 1920s Paris -- were ones you were not in, since you played Owen's present day fiancée.

A: "I know. I was so sad because I love doing period. It's my favorite thing to do. I love vintage clothes and I had just done 'Sherlock Holmes.' But it a great thing to part of and I wish Woody much, much luck coming up."

Q: You seemed to be on a working streak back in 2004 and 2005 with films like "Mean Girls," "The Notebook," "Wedding Crashers" and "Red Eye" among others. Then things slowed down. Did you take a break from Hollywood?

A: "It wasn't deliberate, per se. I had just come off a whirlwind of making movies and I wanted to check in with myself and reflect a little bit on what happened. I had gone through a very big transition. I wish I could be one of those people who could work back to back and not really take a break and not pause for a breath. But I've never been able to do that. It's not my forte, so I tend to always take a little bit of a break."

Q: You are based in Toronto, in your native Canada. When you're on break, what do you do?

A: "There's something (not quite right) when as an actor you're supposed to be interpreting life but you don't know anything about taking the bus. So for me, it's about going into a coffee shop and watching people being people and just getting back out in the world. My job takes me away from my life, my home, my family, my friends, so it's important for me to be able to reconnect, to read books instead of scripts, to cook myself a meal. As fun as it is being on the road and eating room service every night, I appreciate the other things and I always look forward to coming back to them. You really feel like you live two lives sometimes."

(Reporting By Zorianna Kit; Editing by Bob Tourtellotte)

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