MI5 spy records released by the National Archives
Glamorous Nazi spies, German invasion plans, a Nobel Prize winner and links to James Bond.
They all feature in files kept by the British spy agency MI5 that were released by the National Archives.
As war was raging spies were concerned about a 1936 law that said "every German must render service to the Fatherland in time of war".
Gordon Corera has been looking into the historic files.