The nephew of Alan Turing, Dermot Turing, tells the full story of the breaking of the German Enigma Code including the role played by Polish codebreakers and the Polish, French and British secret services that pre-dated the work at Bletchley Park.
The co-operation between Polish, French and British secret services was codenamed X, Y & Z. Turing explains how a Warsaw mathematician began to decipher the communications in the early 1930s and describes how Polish codebreakers had to be extricated from Nazi-occupied France during the war.
Turing is author of Prof, a biography of Alan Turing. He is a trustee of Bletchley Park and an expert on World war II codebreaking. Here he talks to LBC radio host Matthew Stadlen, a former Telegraph interviewer and BBC presenter.