THEATER: Hemingway’s play The Fifth Column takes its now-familiar name from the Spanish Civil War, when General Emilio Mola, advancing on Madrid with four columns of troops, boasted of a hidden “fifth column” of fascist sympathizers waiting within the city. Hemingway, of course, was there for the action as a newspaper correspondent and dashed off the play while fascists bombarded his hotel. His rarely produced drama tells the “surprisingly funny story of the private......