Fraser's first real break was playing Door, in the BBC's dark fantasy series Neverwhere in 1996. She also starred in the 1998 BBC film The Tribe with Joely Richardson and Anna Friel, and played Lavinia in Titus (1999). Other notable film appearances were A Knight's Tale and Vanilla Sky (both in 2001).
She was most recently seen on television starring in two BBC period drama serials, He Knew He Was Right (2004), Casanova (2005) and Reichenbach Falls (2007).
She appeared in the ITV series by Danny Brocklehurst called Talk to Me, in which she played the female lead, Claire Bellington.
Fraser is from Glasgow, and attended Hillhead High School. In 2003 she married Irish-American actor and businessman, Karl Geary.