Nyorai kupfuurira kweiyi ndima - MuHondo Yenyika II Nigel de Grey akapihwa ku "Government Code uye Cypher Chikoro" (GC & CS) paBletchley Park, kwaakaisa pfungwa paGerman traffic yakavharidzirwa pamushini weEnigma cipher. Muna September 1941 akapa mushumo kuna Prime Minister nemashoko okutanga kubva kuzviremera zveGermany kumapoka avo emapurisa anotsvaira misha 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.