Matthew Marsh (born 8 July 1954) is an English actor. He is the older brother of Jon Marsh of the English dance band "The Beloved". He has appeared in the films The Fourth Protocol (1987), Diamond Skulls (1989), Mountains of the Moon (1990), Alambrado (1991), Dirty Weekend (1993), Spy Game (2001), Miranda (2002), Bad Company (2002), Quicksand (2003) and An American Haunting (2005). In 2011 Marsh starred in the biopic film The Iron Lady as the United States Secretary of State Alexander Haig. In 2005, Marsh starred as Simon Hewitt in the first series of The Thick of It.