Emilia Rose Elizabeth Fox (born 31 July 1974) is an English actress whose film debut was in Roman Polanski's film The Pianist. Her other notable films include the Italian–French–British romance-drama film The Soul Keeper (2002), for which she won the Flaiano Film Award for Best Actress; the drama film The Republic of Love (2003); the comedy-drama film Things to Do Before You're 30 (2005); the black comedy Keeping Mum (2005); the romantic comedy-drama film Cashback (2006); the drama Flashbacks of a Fool (2008); the drama film Ways to live Forever (2010); the drama-thriller A Thousand Kisses Deep (2011); and the fantasy-horror drama film Dorian Gray (2009).

Fox's television roles include the BBC drama Pride and Prejudice (1995), the PBS British/German television serial Rebecca (1997), ITV Granada's Henry VIII (2003), BBC's Gunpowder, Treason & Plot (2004), the 2005 BBC miniseries The Virgin Queen (2005) and the ITV crime drama series Fallen Angel (2007). She also appeared as Morgause in the BBC's Merlin, beginning in the programme's second series. Fox also starred in Delicious (2016). She is currently starring as Dr. Nikki Alexander on BBC crime drama Silent Witness, having joined the cast in 2004 following the departure of Amanda Burton. Fox is now the longest serving cast member since the departures of Tom Ward in 2012 and William Gaminara in 2013.

In Britain, Fox has performed in plays with high-profile actors such as Les Liaisons Dangereuses with Jared Harris and Coriolanus with Ralph Fiennes.