Michelle Claire Ryan (born 22 April 1984) is an English actress. She is known for portraying the role of Zoe Slater on the BBC soap opera EastEnders, a role she played from 2000 to 200t, and again from 2025. In 2007, she starred in the short lived revival of the American television series Bionic Woman. She has appeared as the wicked sorceress Nimueh in the 2008 BBC TV series Merlin, and as Lady Christina de Souza in the 2009 episode of Doctor Who, a role she later reprised in various audio dramas between 2017 and 2023, including her own spin-off in 2017.