Meanwhile, back at Carpenter and Quincannon, Professional Detective Services, Sabina is approached with, potentially, the solution to the vexing mystery of the true identity of a man who claims to be Sherlock Holmes. It is vexing because Mr. Holmes has the bad habit—at least in Quincannon’s mind—of dropping in on many of the agency’s cases and, using flawless deductive reasoning, solving them before disappearing again. The estate wants Sabina to find the Sherlock impersonator, whose real name may be Charles P. Fairchild III, so it can determine if he is mentally fit to inherit the estate.
The Plague of Thieves Affair is an adept, entertaining, and intriguing whodunit. Its setting is a well-developed late-Nineteenth century San Francisco. There are several descriptions of the business climate, a quarry with little regard for crushing a house or two to get its desired stone is the best, giving the story a sense reality and place. Quincannon is gruff, intelligent, and deeply in love with Sabina—a name as alluring as any in fiction. Sabina is much less gruff, but just as intelligent as John, with an added air of sophistication. The mystery of the Holmes impersonator is the gem of the story and it nicely unravels with the surrounding investigations. The crimes are solved with a combination of wit and intelligent deductive reasoning. It is as readable as it is satisfying.