I was a bicycle mechanic in Lille when the Germans came. In 1942, the Resistance recruited me because I could repair anything — including a German Enigma component that had been salvaged from a crashed plane. My job was to courier messages between the Pas-de-Calais network and the British intelligence station in London. I bicycled 80 kilometers a week carrying microfilm messages sewn into the linings of my coat. The Gestapo had a photograph of me — taken by a collaborator — that circulated through every police station in northern France. I disguised myself: grew a mustache, changed my posture,...

I worked in the same building where the Room 40 codebreakers had worked during World War I — the Old Building of the Admiralty in London. In WWII, we were a combined British-American operation working on German and Italian naval codes. I had a degree in mathematics from Cambridge — rare for women in 1940 — and I used it to break a cipher system that the Italians thought was unbreakable. We called it 'the Admiral's system.' In 1941, my work contributed to the intelligence that helped sink the Italian fleet at Taranto. That raid was the model for Pearl Harbor. Sometimes I think about that — the ...