Author Tessa Dunlop hosts a one-off, revelatory session with three of the extraordinary women who were involved in Britains most secret wartime operation and feature in her book The Bletchley Girls. Bletchley Park, famous as Britains unprecedented code-breaking organisation, helped the Allies win the Second World War, but that it was predominantly staffed by young girls is less well known. Now in their 90s wireless interceptor Pat Davies, paraphraser Charlotte Webb and bombe operator Ruth Bourne share their wartime stories and the impact Bletchley Park has had on their lives.