The book reveals the story of British Codebreakers from the reign of Elizabeth I to the Cold War. It explores the use of ciphers during the Napoleonic wars, the role of the Royal Mail's Secret Office and the activities the Admiralty's 'Room 40' leading to the creation of the Government's Code and Cypher School.
The main theme of the book are the events of the Second World War and the battle to break the German enigma codes. The center of Britain's...