Watch Channel 4 UK Documentaries online: Episode 21 The Nazi Expedition

In the 1930s, Adolf Hitler's Germany presented a glittering surface sheen of technological modernity. At the annual Nuremberg rallies, fleets of sleek bombers roared over the upturned faces of the Nazi Party faithful. A system of autobahns carried traffic at speed the length and breadth of the Reich. In Berlin in 1936, a magnificent stadium housed the Olympic Games. But beneath the tread of marching feet and the rumble of tanks on Nuremberg's Zeppelin Field, there pulsed the rhythms of a different and much older set of beliefs, a philosophy that animated the Nazi Party's early ideologues and, crucially, the man who stood behind Hitler himself – Heinrich Himmler, chief of the SS. These beliefs were anything but technological. They were a curious mixture of ancient Teutonic myth, Eastern mysticism and late 19th-century anthropology. Whether Adolf Hitler took them wholly seriously is open to debate. But Heinrich Himmler certainly did. They lay at the heart of the SS empire he created and which became the most dreaded arm of the Nazi state. They were also the mainspring behind a Nazi expedition to secure the secrets of a lost super-race in the mountains of Tibet.

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