Morton was a member of the Central Junior Television Workshop in her native Nottingham, and later began her career in British television in 1991. She guest-starred in "Soldier Soldier" and "Cracker" and had a bigger role in the ITV series "Band of Gold". She made the transition to film with lead roles in the dramas "Emma" (1996), "Jane Eyre" (1997), and the well-received "Under the Skin" (1997). Morton also starred alongside Max Beesley in BBC's mini series production of 'Tom Jones, A Foundling' in 1997 to critical acclaim. The next year, Woody Allen cast Morton in "Sweet and Lowdown" (1999), which earned her nominations for the Academy Award and the Golden Globe Award for Best Supporting Actress.