Her debut performance was in Harry Potter and the Philosopher's Stone (2001) as Ron Weasley's little sister Ginny Weasley, although her role got bigger in the later Potter films, even becoming Harry's love interest.

In 2002, she did the Hallmark TV film Stranded (2002) and then in 2004 was cast in a BBC film Agatha Christie: A Life in Pictures (2004) as Young Agatha.