[citation needed] She attended Queen's University in Kingston, Ontario, where she won the Lorne Greene Award for outstanding work in the theatre.

[3] When she returned to Canada, Crewson landed a leading role in the television movie War Brides (1980) directed by Martin Lavut, for which she received her first ACTRA Award nomination.

She also received Gemini Awards nomination for I'll Never Get to Heaven (1992), A Killing Spring (2002), Sex Traffic (2004), The Robber Bride (2007), and The Summit (2008), and won for At the End of the Day: The Sue Rodriguez Story (1999), The Many Trials of One Jane Doe (2002), and The Man Who Lost Himself (2005).

[9] She also appeared in Gang Related (1997), played a leading role in Sleeping Dogs Lie (1998), and co-starred opposite Robin Williams in the science fiction film Bicentennial Man (1999).

[9] She also appeared in Between Strangers (2002), The Clearing (2004), Eight Below (2006), The Covenant (2006), Academy Award-nominated Away from Her (2006), The Seeker (2007), Winnie Mandela (2011), Antiviral (2012), Into the Forest, Room (2015), Kodachrome (2017), and On the Basis of Sex (2018).

Other credits including Lives of Girls & Women (1996), Summer's End (1999), The Matthew Shepard Story (2002), An Unexpected Love (2003), Twelve Mile Road (2003), and The Path to 9/11 (2006).

From 2000 to 2002, she played Joanne Kilbourn, a single mom of three and an ex-cop who teaches criminology and solves crimes in her spare time, in six movies based on novels by Gail Bowen.

[4] In 2003, Crewson took a recurring role as Dr. Anne Packard, personal physician and love interest to the President, of the third season of Fox drama series 24.

[14] In 2016, she received the Earle Grey Award, which recognizes actors for their contributions to the international profile of Canadian TV or for their significant body of work.

[15] From 2017 to 2021, Crewson played a recurring role lead character's mother and assisting her in investigations in the CBC drama series, Frankie Drake Mysteries.

In 2018, she starred in the CTV crime drama series, The Detail, for which she was nominated for a Canadian Screen Award for Best Actress in a Continuing Leading Dramatic Role.

[19][20] She later was cast in the third season of CBC Television police drama Pretty Hard Cases and the internationally produced thriller Gray.