Recounts the true story of how a team of Allied codebreakers, spies, and Navy soldiers broke the Nazi code and helped tip the scales in favor of the Allies during World War II. Profiles the different individuals involved and their contributions. Includes an epilogue, photographs, and a timeline.

Traitor -- The starting line -- The machine and the method -- Recklessness -- The violence of words -- A four-character answer to a six-word question -- As by magic -- The Gale -- Verdier -- Fahrenheit 451 -- Two more rotors -- What Langer didn't say -- Il y a du nouveau -- Harry Hinsley -- Escape -- Führer der U-boote -- Pay him -- Bletchley Park -- Uncles -- Phony war -- A missing rotor -- Dark -- Certain mechanical devices -- Nearly drowned -- Bombes and spider bombes -- Hunting at night -- Joan -- Operation Ruthless -- Doubt -- Asché -- Operation Paula -- Refusal to exit -- Yet another home -- U-boat peril -- Somali -- Weather ships -- Tides turn -- Interlude -- Churchill -- Shark in the water -- Losses and Laconia -- U-559 and Petard -- Kisses -- A family name -- The fall of Cadix -- Jadwiga's strength -- Found -- I was expecting you tomorrow -- Schmidt -- Bertrand -- Epilogue -- Timeline.