Holmes and Watson are on the trail of seemingly unrelated deaths preceded by sudden unexplained madness as they work to solve the case of the abominable worm. Are the deaths murders? And if so, what is the motive and who is responsible? Can Holmes and Watson solve the mystery of the abominable worm before her Majesty's navy experiences an unprecedented two-fold loss.

Rebecca St. John has established herself as a force to be reckoned with in London's mysterious spiritual world and the hidden world of London's private clubs. But she wants more. She wants to be the next Professor Moriarty and she has the brains, the looks, and the drive to succeed if she can outwit Holmes and bring her first large scale criminal scheme to a successful conclusion.

Join Holmes, Watson, Mycroft, Inspector MacDonald and the Baker Street Irregulars on a cat and mouse high stakes game of mystery and deduction. This time, the game is afoot, and she is a formidable opponent indeed.