April 1945. As Allied bombs rain down on Europe, a 400-year-old institution looks set to be wiped off the face of the Earth. The famous white Lipizzaner stallions of the Spanish Riding School in Vienna, unique and precious animals representing centuries of careful breeding, are scattered across rural Austria and Czechoslovakia in areas soon to be swallowed up by Soviet forces – there, doubtless, to become rations for the Red Army.

Their only hope lies with the Americans: what if a small, highly mobile US task force could be sent deep behind German lines, through fanatical SS troops, to rescue the horses before the Soviets arrive. Just five light tanks, a handful of armoured cars and jeeps, and 300 battle-weary GIs must plunge headlong into the unknown on a rescue mission that could change the course of European history.

So begins Operation Cowboy, the greatest Second World War story that has never been fully told. GIs will join forces with surrendered German soldiers and liberated prisoners of war to save the world’s finest horses from fanatical SS and the ruthless Red Army in an extraordinary battle during the last few days of the war in Europe.