Alex Kingston
From Tardis Wiki, the free Doctor Who reference
Alex Kingston (born Alexandra Kingston on 11th March 1963) played Professor River Song in Silence in the Library and Forest of the Dead. A Royal Academy of Dramatic Arts-trained actress, Kingston is best known internationally for her role as Dr. Elizabeth Corday in the US TV series ER and the title role in the 1996 film The Fortunes and Misfortunes of Moll Flanders.
Formerly married to actor Ralph Fiennes, whom she met at RADA, she is currently married to Florian Heartel and has one child.