From 2000 until 2002, Marsh appeared in "The Ghost Hunter". Her many stage credits included the West End stage revival of "Boeing Boeing" at the Comedy Theatre in 2007 and in Peter Hall's production of "The Portrait of a Lady" in 2008. She made an appearance in the 2008 BBC adaptation of Jane Austen's "Sense and Sensibility"; played the recurring character Lizzie Galbraith alongside Joanna Lumley as Davina Jackson (the lead character) in Babycow Productions' "Sensitive Skin" which aired on BBC Two in 2005 and 2007. She appeared in BBC Four's "Crooked House" in December 2008 in a role especially written for her by Mark Gatiss.