After the end of World War II, Alexander returned to his position as head of research at the John Lewis Partnership, but quickly realised that code breaking was a far more exciting occupation.
Pagkatapos ng dulo ng World War II, Alexander ibabalik sa kanyang posisyon bilang pinuno ng mga pananaliksik sa John Lewis Partnership, ngunit mabilis na realised na code ng pagbubukas ay isang malayo mas nakapupukaw ng trabaho.