The 23rd Headquarters Special Troops, known as the 'Ghost Army,' was a top-secret Allied unit composed of artists, actors, and sound engineers. Their mission was to deceive the German army by creating the illusion of massive troop concentrations where none existed. They used inflatable rubber tanks, trucks, and airplanes that looked realistic from the air. To complete the ruse, they played recordings of armored divisions on powerful speakers and transmitted fake radio traffic. During the crossing of the Rhine and the Battle of the Bulge, they successfully diverted German forces away from actual Allied units. Their work remained classified for decades after the war and is estimated to have saved between 15,000 and 30,000 American lives.