During World War II, a top secret program (codename Ultra) housed at Bletchley Park cracked the German Enigma (and later the Lorenz) cyphers, providing crucial intelligence for the war effort. It is estimated that the work of the codebreakers shortened the war by two years and saved countless lives.
Because of the Secrets Act, the efforts of these quiet heroes went largely unrecognized until the late 1990's. Keeping the secret was so important that the UK for decades did not own up to the fact that they had built the first digital computer (Colossus) years before the US.
As word leaked out about the work at BP in the late 1990's, words like Colossus and Bombe and names like Turing and Keen became household words. But while these luminaries led the charge, Bletchley Park's work required thousands of individuals at every level - from mathematics to running the mailroom.
While Turing and the like were very famous, most people were not - but they were just as important to the war effort.
This is their story.