Video report by ITV News Reporter Stacey Foster
To the residents of the sleepy Cotswold village of Great Rollright during the Second World War, Mrs Burton was the neighbour who baked them scones. But to her handlers in Moscow, she was Colonel Kuczynski of the Red Army. It is a fascinating true story of a Russian spy who almost killed Adolf Hitler and juggled her work with being a wife, mother and lover. One of the reasons Agent Sonya got away with it for so long was the British Secret Service assumed the spy they were trying to track down was a man.
The life and times of Colonel Ursula Kuczynski has been told in a new book 'Agent Sonya' by Ben Macintyre, who reveals how the dedicated communist managed to go undetected for so long.