Set in fourth-century B.C. Greece, The Mask of Apollo is narrated by Nikeratos, a tragic actor who takes with him on all his travels a gold mask of Apollo, a relic of the theater's golden age, which is now past. At first his mascot, the mask gradually becomes his conscience, and he refers to it his gravest decisions, when he finds himself at the center of a political crisis in which the philosopher Plato is also involved. Much of the action is set...