It takes two fictional sleuths to engineer Professor Moriarty’s comeuppance.
In a letter to Dr. Watson written 20 years after Holmes met Moriarty at Reichenbach Falls, Thomas Carnacki, the detective who solved supernatural cases using the principle of the electric pentacle, recounts how an apparently chance encounter with one Anna Schmidt led to their picnicking at the Falls just in time to rescue one man who had been pushed over by the other. Dubbing the amnesiac survivor Harold Silence, the couple whisk him off to Prefargier Sanatorium in Meiringen, Switzerland. Unfortunately, the survivor’s nemesis, having preceded him there, continues his attempts at murder, though he seems loath to harm Anna. Small wonder: As Anna later relates en route to Paris, the man is her father, Professor James Moriarty, who, using algorithms developed by his late wife Susanna, had killed Jack the Ripper, only to have the Ripper’s demon essence invade his body and corrupt him. The only man who can stop him now is the great Sherlock Holmes, aka Harold Silence. Once he recovers his memory with boosts from the electrical machine Carnacki has stolen from the Swiss sanatorium, the game is afoot, with disguises, deductions and death in attendance.
Sherlockians may quibble at their hero’s fallibility, but King (The Angel of Death in Chicago, 2008, etc.) could well create new fans for William Hope Hodgson’s early sci-fi tales of Carnacki.