In 2003, Duggan played the part of Little Cossette in the hit stage show Les Misérables at the Palace Theatre, London. She played the lead roles in two short films: Amanda in Between Us (2004), and Ellie in Spoilt Eggs (2006).
Duggan first appeared on screen as Lauren Branning in the BBC soap opera EastEnders on 3 July 2006. She was dropped from the show in May 2010 by executive Producer Bryan Kirkwood and was replaced by Jacqueline Jossa.
In 2010, Duggan played Emily in the film Rules of Love, performing in one of the songs. She appeared in two episodes of the 2012 series of BBC One's long-running drama Silent Witness. In October 2011 it was announced that she would be starring in feature film Everyone's Going To Die. In 2016 Duggan had a small role in The Tunnel Sabotage.
