Europe in the midst of World War II: Adolf Hitler’s Stukas and Panzers have stormed across most of the continent. This new kind of mechanized warfare moves faster and hits harder than anything the world has ever seen. To stop it, the Allies need to starve it of fuel. The German-held oil refineries in Ploesti, Romania become a prime target for American bombers.
The Germans defend the refineries with ferocious zeal. Their fighter planes and anti-aircraft artillery often blow bombers out of the sky as they transit over Yugoslavia on the way to or from Ploesti. Surviving crewmen parachute into the green hills of Yugoslavia.
On the ground, they find themselves surrounded by a civil war in the midst of a world war. Chetnik and Partisan guerrillas battle each other when not fighting the occupying Nazis. Both factions shelter the downed airmen, and the number of stranded fliers grows into the hundreds.
With so many American airmen in enemy territory, it’s only a matter of time before the Germans catch on. The fliers—and anyone who helps them—could find themselves at the mercy of the Gestapo.
The U.S. Office of Strategic Services—a forerunner of the Central Intelligence Agency—organizes a rescue plan. Agents parachute into Yugoslavia to coordinate the construction of dirt airstrips. The Yugoslav fighters, along with local villagers and the downed fliers, build clandestine airstrips by hand. In an audacious mission known as Operation Halyard, aircrews fly in on C-47 Skytrains, the military version of the DC-3. They recover more than 500 aviators. Operation Halyard goes down in aviation annals as one of the greatest—and least known—rescues in military history.