Stephen Dillane (born 27th March 1957) is a British actor experienced with roles on both stage and screen. He is arguably best known for his Emmy-nominated performance as Thomas Jefferson in the HBO mini-series John Adams. He has also appeared as Leonard Woolf in The Hours, Merlin in King Arthur and Horatio in the Mel Gibson-starring version of Hamlet.
His son, actor Frank Dillane, portrayed the teenage Lord Voldemort in the film adaptation of Harry Potter and the Half-Blood Prince.
In Game of Thrones Dillane played the role of Stannis Baratheon. He was announced in the role on 19 July 2011 and is part of the starring cast for the second, third, fourth, and fifth seasons. Although he plays Robert Baratheon's younger brother, Dillane is actually eight years older than Mark Addy, who portrayed Robert.