Terry McCabe delivers crisp, engrossing adaptations and stagings of two Sherlock Holmes mysteries. "A Scandal in Bohemia" is peculiarly passionate, as Sir Arthur Conan Doyle's genius detective (Don Bender, both smooth and driven) meets his emotional match in a beautiful American actress (Meghan Principe). And in "The Final Problem," a riveting depiction of good and evil locked in mortal combat, he meets his ultimate opponent: Professor Moriarty, the "Napoleon of crime" (played by Bender as if he were Holmes's alter ego). Holding this world together is Will Schutz's redoubtable Dr. Watson, who both narrates and doubles nicely as the blackmailed King of Bohemia. One more actor might have fleshed out the storytelling agreeably. But who can truly regret a tour de force? Through 6/4: Fri-Sat 8 PM, Sun 3 PM, City Lit Theater Company, Edgewater Presbyterian Church, 1020 W. Bryn Mawr, 773-293-3682, $25.