The vital role played by Polish exiles during the Battle of Britain, who represented one in eight Allied pilots and whose 303 Squadron boasted the best hit rate against the Luftwaffe, is today common knowledge. As is the role Polish forces played in breaking the siege of Monte Cassino, and the daring raid on Dieppe in 1942. A lesser known Polish contribution towards the Allied victory in 1945, but equally significant, is the battle that took place inside the minds of Poland’s finest academics to crack the German Enigma code. It all began in Poznań, namely in the mathematics class of the university. Ace students Jerzy Różycki, Marian Rejewski and Henryk Zygalski came to the attention of Polish intelligence services on account of their excellent German skills and sharp mathematical minds. Recruited to attend cryptology courses in Warsaw alongside 17 other Poznań University alumni, the three were set to work in 1932 on cracking German ciphers. It was here they made the first vital Engima breakthrough using a mathematical theorem since described as ‘the theorem that won WWII.’ On the day before the Nazi invasion of Poland the three fled to Romania where they immediately sought contact with the Allies. Originally they turned up at the British Embassy in Bucharest, but having been told to ‘come back in a few days’ decided to try their luck with the French instead. This proved more successful and from there they found themselves in France, working in Cadix, a secret intelligence cell operating in the unoccupied south. With the risk of discovery by the Germans growing greater the team were forced to flee. Różycki drowned at sea in 1942 after the boat carried him sank in suspicious circumstances, Zygalski and Rejewski however made it to Spain, in spite of being robbed by the man guiding them over the Pyrenees.