A lost city. A thousand-year-old mystery. A quest that changed history.

Beneath the plains of Afghanistan lie the remains of a fabulous city: Alexandria Beneath the Mountains, founded by Alexander the Great. For centuries, it was a meeting point of East and West. Then it vanished.

In 1833, it was discovered by the unlikeliest person imaginable: Charles Masson, spy, archaeologist, deserter, and the greatest of nineteenth-century travelers.

On the way into one of history's most extraordinary stories, Masson would take tea with kings, travel with holy men and become the master of a hundred disguises. He would spy for the British East India Company and be suspected of spying for Russia at the same time. He would starve, talk his way out of prison and flee assassins. He would see things no westerner had glimpsed before and few have glimpsed since.

Masson discovered tens of thousands of pieces of Afghan history, including the 2,000-year-old Bimaran golden casket, which has upon it the earliest known face of the Buddha. On the plains outside Kabul, where Bagram Airbase stands today, he uncovered Alexander's lost city. He would be offered his own kingdom; he would change the world, and the world would destroy him.

This is an astounding journey through nineteenth-century India and Afghanistan, a world of espionage and dreamers, murder, betrayal, and boundless hope. At the edge of empire, amid the deserts and the mountains, The King's Shadow is a story about how our wildest dreams can change the world.