On May 13, 1935, a small convoy-two Royal Air Force lorries, a couple of cars, six men-pulled into the seafarers' village of Orford, about 150 kilometers northeast of London. Armed with some crude equipment, the men quickly set up shop in abandoned air force huts. Their secret mission: to save the United Kingdom from air attack. It was almost five years to the day before Hitler's invasion of Western Europe. But their early start developing the technology now known as radar proved critical in warning of approaching bombers in the Battle of Britain-saving thousands of lives and ultimately forcing the Nazis to abort plans to invade Great Britain.

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