When the sacred relics and mystical objects of London begin disappearing, Sherlock Holmes must call on more than his powers of deduction to solve a mystery that threatens the safety of the British Empire and Doctor Watsons mortal soul.

In a new novel of supernatural adventure, Sherlock Holmes faces his greatest challenge, to locate and defeat the wraith of a powerful wizard. With the assistance of an incorruptible saint, an immortal librarian, a troupe of ghosts, a Scotland Yard Inspector, and, of course, Dr. Watson, Holmes finds himself in a race against time to protect both the human world and the Shadows from 'the most evil man who ever lived.'