Wow! To learn about the brainpower and tenacity of a woman cryptographer who worked in both World Wars and worked on monster cases in between was quite impressive. It always astounds me that I have never heard of so many people whose talents and jobs had a direct impact on the lives of so many.  This was kind of hard to listen to with so many names to keep track of and I am sure there were photos to show the rotor machines and some of the codes.