William Thomas
From Tardis Wiki, the free Doctor Who reference
William Thomas played Martin in TV: Remembrance of the Daleks, Cleaver in TV: Boom Town and Geraint Cooper in TV: Something Borrowed, TV: The New World, TV: The Categories of Life, TV: The Middle Men, TV: The Gathering and TV: The Blood Line, making him one of the few actors to star in both the classic and new series of Doctor Who.
Indeed, he is the first actor to appear in both the classic and revived series of Doctor Who. Furthermore, he is the only actor to appear in both of those series and Torchwood.
