Perched like a black crow on a crag in the most hostile depths of the Himalayas stands a monastery. For a thousand years the monks have kept guard. Now their sanctum has been violated, the secret carried off. After a millennium of hiding from the world, the guardians of the treasure will have to turn to an outsider for help.

Luckily Special Agent Aloysius Pendergast is no stranger. Having trained body and mind in Tibet, he knows the land well. But neither he nor his ward, Constance, are prepared for the truth about what the monks have been protecting.

The pursuit of the stolen artefact takes Pendergast and Constance far from the snowy wastes, to where the largest-ever ocean liner is preparing for her maiden voyage. As the ship slips into the night, it becomes a deadly race to recover the secret of the monks, or blackness to threaten to fall not just over the ship, but the wider world.