The Spanish Inquisition looms large in Kaplan's By Fire, By Water. The central character, Luis de Santangel, a powerful courtier to the Spanish monarchs Ferdinand and Isabella, is a Christian of Jewish descent who begins to rediscover the faith of his ancestors in the course of the novel. He also becomes involved with a Jewish woman living in the Muslim state of Grenada, Judith Migdal.
However, Luis goes to great lengths to protect his appearance of a dutiful Christian servant of the King and to avoid running afoul of the Inquisition, even taking some morally questionable actions.
I greatly enjoyed this novel, but its conclusion was far from happy. The characters suffer a great deal in this novel, as might be expected in consideration of the themes. The author has also maintained a good deal of historical accuracy, which makes the characters feel more believable and real.