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How the British and Americans started listening in – BBC News

How the British and Americans started listening in – BBC News

It was late on 8 February 1941 when four Americans arrived at Bletchley Park. Black-out curtains made the mansion appear even darker. The journey of the four – known as the Sinkov mission after their leader Abraham Sinkov – had been stormy, dangerous and utterly secret.Their arrival marked the opening courtship of what would become the longest standing – and occasionally controversial – intelligence alliance in history.

Source: How the British and Americans started listening in – BBC News