Pedzisa mutsara unotevera: MuHondo Yenyika II Nigel de Grey akapiwa basa ku"Government Code and Cypher School" (GC&amp;CS) paBletchley Park, kwaakaisa pfungwa dzake pakushambadzira kweGermany kwakanyoreswa pamushini weEnigma. Muna September 1941 akapa mushumo kuna Prime Minister nemashoko okutanga kubva kuzviremera zveGermany kumapoka avo emapurisa
kuputsa misha nenzira yakarongwa uye kubvisa vagari vayo. Chimwe chiratidzo chakazvirumbidza pamusoro pokuurawa kwavanhu 30 000 "munzvimbo huru". Zvichitevera nyevero yakaitwa muhurukuro kuparamende naChurchill, chirevo cheGermany muna October 1941 chakayambira kuti hapanazve nongedzero ku"mabasa akaoma" dzinofanira kuitwa panhepfenyuro dzisina waya.