This unique new volume analyses source documents both previously known and recently declassified, generating an extremely broad and original synthesis about Enigma.The author uses his experience as a cryptologist to fill in gaps in the sources or to correct misguided interpretations, also adding the passion of a journalist, drawing a vivid picture of the characters and the story. As a Pole, he presents this story through the lens of the fate of the Polish mathematicians who were the first to break the cipher as early as 1932 and laid the foundations for the subsequent Allied success.The book's coverage ranges from the mathematical foundations of codebreaking, through the complex fates of the people and organisations involved in the attacks on the Enigma ciphers, the impact of decrypts on the fate of the major campaigns of the Second World War, to the role that wartime cryptology and codebreakers played in the birth of digital civilisation. The Polish mathematicians' story is presented in the full context of the struggle with the cipher, including the complex interplay between codebreakers, military commanders and politicians of the UK, US, Poland, France, and the Third Reich.By looking at events through the eyes of a cryptologist rather than solely as a historian, the reader is given a glimpse into the backstage of the cryptologic workshop; a better understanding of the scale and nature of the challenges codebreakers faced; and insights into their responses to those challenges, as well as the emotions, dilemmas, disappointments, and triumphs involved.