Sophia Jane Myles (; born 18 March 1980) is an English actress, best known in film for portraying Erika in Underworld (2003), Lady Penelope Creighton-Ward in the live-action Thunderbirds film, Isolde in Tristan & Isolde and Darcy in , and has received critical acclaim for her television work, particularly as Madame de Pompadour in the Doctor Who episode "The Girl in the Fireplace" and Beth Turner in Moonlight.