When she moved to Los Angles, she auditioned to play Nancy Drew in a TV pilot, but didn't get the job. However, being devastated over losing the pilot helped her land her first American movie, The Hot Chick.
"It allowed me to be really relaxed," McAdams, 37, tells PEOPLE in an exclusive video.
Having to switch bodies with Schneider made The Hot Chick "one of the hardest jobs I've had to date," she says.
McAdams has come a long way from The Hot Chick. At this year's Academy Awards, she's nominated for Best Supporting Actress for her performance as Boston Globe reporter Sacha Pfeiffer in Spotlight.
Finding her character was easy because she spent a lot of time with the real Sacha Pfeiffer.
"It was great I had such a direct link to the person I was playing," she says. "She never makes the story about herself. She's such a compassionate listener. She allows people to feel comfortable to open up to her. So, I wanted to do justice by her and tell the story as honestly as possible."
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