The fascinating, untold story of how British intelligence secretly used homing pigeons as part of a clandestine espionage operation to gather information, communicate, and coordinate with members of the Resistance to defeat the Nazis in occupied Europe during World War II.

Between 1941 and 1944, British intelligence dropped sixteen thousand homing pigeons in an arc across Nazi-occupied Europe, from Bordeaux, France to Copenhagen, Denmark, as part of a spy operation code-named Columba. Returning to MI14, the secret government branch in charge of the ''Special Pigeon Service,'' the birds carried messages that offered a glimpse of life under the Germans in rural France, Holland, and Belgium. Written on tiny pieces of rice paper tucked into canisters and tied to the birds’ legs, these messages were sometimes comic, often tragic, and occasionally invaluable—reporting details of German troop movements and fortifications, new Nazi weapons, radar systems, and even the deployment of the feared V-1 and V-2 rockets used to terrorize London.

The people who sent these messages were not trained spies. They were ordinary men and women willing to risk their lives in the name of freedom, including the ''Leopold Vindictive'' network—a small group of Belgian villagers led by an extraordinary priest named Joseph Raskin. The intelligence Raskin sent back by pigeon proved so valuable that it reached Churchill and MI6 parachuted agents behind enemy lines to assist him.

Gordon Corera uses declassified documents and extensive original research to tell the story of the Operation Columba and the Secret Pigeon Service for the first time. A powerful tale of wartime espionage, bitter rivalries, extraordinary courage, astonishing betrayal, harrowing tragedy, and a quirky, quarrelsome band of spy masters and their special mission, Operation Columba opens a fascinating new chapter in the annals of World War II. It is ultimately, the story of how, in one of the darkest and most dangerous times in history, under threat of death, people bravely chose to resist.