In 2010, McAdams appeared in her first star vehicle, the comedy Morning Glory.
After graduating from a four-year theatre program at York University in 2001, she initially worked in Canadian television and film productions such as the drama film Perfect Pie 2002 for which she received a Genie Award nomination , the comedy film My Name Is Tanino 2002 , and the comedy series Slings and Arrows for which she won a Gemini Award.
In 2002, she made her Hollywood film debut in the comedy The Hot Chick.
McAdams rose to fame in 2004 with her roles in the comedy Mean Girls and the romantic drama The Notebook.
After a two-year career break, McAdams appeared in two limited release films in 2008; the film noir Married Life and the road trip comedy-drama The Lucky Ones.
She returned to prominence in 2009 by appearing in the political-thriller State of Play, the science-fiction romantic drama The Time Traveler's Wife and the mystery action-adventure film Sherlock Holmes.
For her performance in Spotlight, she was nominated for the Academy Award for Best Supporting Actress.