Poland. French and British cryptoanalysts arrive at the headquarters of Biuro Szyfrow, who had been tasked years earlier with trying to decrypt Enigma. He had hired the country’s best mathematicians, including Marian Rejewski, who started by identifying some weaknesses: repetition is the enemy of security, for example. Repetition leads to patterns, which are a godsend for cryptanalysts. For example, the Enigma key is encoded twice at the beginning of each message. By also analyzing the mechanical structure of the Enigma machine, he then manages to make the problem 10 billion times easier than it was initially. Then, using other “tricks,” such as partially decoded phrases that can be guessed, like “alliveinbelrin” (arriving in Berlin), he adds the finishing touches. The Poles were thus able, by the early 1930s, not without a huge decoding effort, to decode the current version of Enigma (which, however, would later be made much more complex). When Hermann Göring visited Warsaw in 1934, he was completely unaware that his communications were clear to the Poles. When the French and British realized this on July 24, 1939, they realized how far the Poles had come, already for almost a decade and with very limited funds, and they were astonished, especially the French. As a final surprise, the Poles offered them one of the two Enigma machines they had available. It would leave first for Paris and then for London on August 16th, among the luggage of the famous actress Yvonne Printemps, so as not to arouse suspicion among the German spies monitoring the ports. Two weeks later, World War II will begin, and cracking the Enigma code will make all the difference in the world…
