For much of the cinema’s history, the movies have had the good sense to keep Sherlock Holmes’ nemesis Professor Moriarty off camera, an unseen menace made all the more menacing by his absence.
But Guy Ritchie’s “Sherlock Holmes: A Game of Shadows,” puts the infamous Professor M. face to face with his foe, Holmes. They quarry, trade threats and play chess. But as the evil genius is played the unimposing Jared Harris (“Mad Men,” “The Curious Case of Benjamin Button”), you can’t help but wonder why Robert Downey Jr. doesn’t just dope-slap this shrimp and “crack on.”

