There are more ways than ever to listen to History Daily ad-free.

Listen with Wondry Plus in the Wondry app.

As a member of NoisorPlus at noisor.com or in Apple Podcasts,

or you can get all of History Daily plus other fantastic history podcasts at IntoHistory.com.

Yesterday. Yesterday was the 81st anniversary of one of the most consequential military operations in history, D-Day.

It was daring and dangerous, a massive, coordinated, multinational invasion of mainland Europe. It was the Allies' best and

maybe last chance to turn the tide of the war against Nazi Germany, and to be successful,

it required precision, planning, and perfect secrecy. We have no real way of knowing what would

have happened if D-Day failed, but certainly Winston Churchill thought he had an idea.

Decades earlier, as First Lord of the British Admiralty during World War I,

Churchill had championed his own D-Day-style invasion at Gallipoli, and it was a disaster.

This failed campaign against the Turks lasted nine months, ended in retreat, cost both sides 500,000 casualties,

and all but ended Churchill's political career. So it's no wonder that he was anxious about

another amphibious invasion years later in 1944. But he wasn't the only one who had reservations.

Everyone did. D-Day, if it happened, would be the largest seaborne invasion

the world had ever seen, requiring men and resources that America and Britain did not have

when planning began in earnest in 1943. So to ensure success, they employed every trick in the book

and quite a few new ones. The Allies hatched an elaborate plan to throw Hitler off the

scent, building fake tanks, fake planes, even an entire fake army. Two British commandos

carried out a daring intelligence gathering mission right under the Germans' noses, and as Dede

approached, an eccentric double agent sent the most important secret message of his life.

On today's Saturday matinee, we bring you the story of the espionage that kept D-Day secret,

...