Wulf Schmidt

Wulf Dietrich Christian Schmidt, later known as Harry Williamson (7 December 1911 – 19 October 1992) was a Danish citizen who became a double agent working for Britain against Nazi Germany during the Second World War under the codename Tate. He was part of the Double Cross System, under which all German agents in Britain were controlled by MI5 and used to deceive Germany. Nigel West singled him out as "one of the seven spies who changed the world." Provided by Wikipedia