The Revenge of Moriarty — John E. Gardner

San Francisco 1896. The foggy mists are lifting, and who should emerge from the sinister back alleys to reclaim his title as the most dangerous scientific criminal of his time but the nefarious Professor James Moriarty! Rising like a wicked phoenix from the ashes of his own destruction. Moriarty vows to launch a vendetta against the European underworld leaders who turned on him and left him in the clutches of Sherlock Holmes.

Back to London to take revenge! Baiting them with their favorite vices--spectacular German jewels, a delectable Italian beauty, the prized Mona Lisa, a very accommodating servant girl--Moriarty plays on their sinful weaknesses, and one by one ropes them in as only he can. Then, daring to commit his most horrible scheme, the professor masterminds a plot to destroy the legendary Holmes by cutting off his cocaine supply and bringing him to public disgrace.

Is there no stopping them dastardly genius? Does this really mean the end of the Baker Street Sleuth--and a gruesome triumph for Professor Moriarty??