In the winter of 1941, as Britain faced defeat on all fronts, an RAF pilot photographed an alien-looking object on the French coast near Le Havre. The mysterious device—a "Wurzburg Dish"—appeared to be a new form of radar technology, pointed directly across the English Channel. Persuaded of the threat, Winston Churchill directed his Special Air Service to lead Operation Biting, an extraordinary "snatch-and-grab" raid on Germany's secret radar installation. Led by the legendary Major John Frost and aided by the French Resistance, these paratroopers would risk all in a daring airborne assault, and as the author of SAS Nazi Hunters details, the outcome of the war hung in the balance.