A Bletchley Park ya yi aiki a kan ƙididdigar ƙididdigar Enigma har sai mutuwarsa a 1943. Ya gina tawagar kuma ya gano hanyar da ta karya Italian Naval Enigma, samar da bayanan sirri da aka yaba da nasarar Allied a
Yaƙin Cape Matapan. A shekara ta 1941 Knox ya karya Abwehr Enigma. A karshen yakin, Knox Intelligence Service ya yada 140,800 Abwehr decrypts, ciki har da bayanan sirri da ke da muhimmanci ga D-Day.