When a private envoy of the queen and member of Lord Carmichael's discreet service goes missing, Balfour and Meriwether are asked to look into the affair. They will find a labyrinth of dreams, horrors risen from hell, prophecy, sexual perversion, and an abandoned farmhouse on the moors outside Harrowmoor Sanitarium. The earth itself will bare its secrets and the Empire itself will tremble in the face of the hidden dangers they discover, but the greatest peril is the one they have brought with them.