"What role can or should loyalty play in the life of a police inspector? It's a question Commissario Guido Brunetti must face and ultimately answer in Give unto Others, Donna Leon's splendid thirty-first installment of her acclaimed Venetian crime series. Brunetti is approached for a favor by Elisabetta Foscarini, a woman he knows casually, but her mother was good to Brunetti's mother, so he feels obliged to at least look into the matter privately,...