Raoul Wallenberg was a heroic Swedish diplomat who made history by assisting and saving thousands of Jews in Budapest during the Holocaust. But Wallenberg was arrested by the Soviet Union and disappeared into the Gulag, never to return home to his family, or his own future.

One of the most admired figures from Holocaust history, Raoul Wallenberg is also one of the most enigmatic. Why did this scion of Sweden's most important family go to Budapest to save Jews during the Holocaust? And, once there, what did he actually do to save lives?

As a young Swedish diplomat serving in Budapest during the Second World War he saved thousands of Jews by providing them with "protective passports" issued by Sweden's government.

But, at the war's end, he was spirited away by the Soviets and died, if their reports are to be believed, on 17 July 1947 somewhere in the cavernous, pitiless surroundings of the KGB's Lubyanka Prison in central Moscow.