検索キーワード： "David Park" グレートブリテン

Since the secret of Bletchley Park was revealed in the 1970s, the work of its codebreakers has become one of the most famous stories of the Second World War. But cracking the Nazis' codes was only the start of the process. Thousands of secret intelligence workers were then involved in making crucial information available to the Allied leaders and commanders who desperately needed it.

The World War II codebreaking station at Bletchley is well known and its activities documented in detail. Its decryption capabilities were vital to the war effort, significantly aiding the Allied victory. But where did the messages being deciphered come from in the first place? This is the extraordinary untold story of the Y service, a secret even more closely guarded than Bletchley Park. 'Y service' was the code for the chain of wireless intercept stations around Britain and all over the world.

Planning the invasion of Normandy, the Allies knew that decoding the communications of the Nazi high command was imperative for its success. But standing in their way was an encryption machine they called Tunny (British English for “tuna”), which was vastly more difficult to crack than the infamous Enigma cipher.