Bletchley Park was - so we're told - staffed by a majority of women, who had menial roles while a handful of pipe-smoking male boffins did the brainy codebreaking stuff. As with many urban myths, it's not true: women as well as men had serious full-on codebreaking roles. And not just at Bletchley, but in codebreaking agencies in the US and even in Germany. Yet, when the histories were written, the codebreaker women somehow got left out. Who were they? What did they achieve? How come they vanished? What happened to them after the war?