In 1966, a group of battle-weary American GIs trekked through the Vietnamese jungle knowing each step could mean facing the enemy's guns. But instead of ambush, they stumbled upon a hidden treasure beyond their wildest dreams. It was a discovery that exacted a terrible cost.

A vacation spot picked at random, Thailand is intended to provide relaxation time for globe-trotting archaeologist Annja Creed. Yet the irresistible pull of the country's legendary Spirit Cave lures Annja and her companions deep within a network of underground chambers--nearly to their deaths. The ancient burial sites have slumbered through the ages. Yet no rest is found there--just the voices of the dead. When the dead speak, will they help Annja uncover the perplexing past of a remarkable find or will they call her to join them?