From the beginning the bright and articulate English teacher and the tall, strong, and equally bright minister sense they are different, but they assume they can still enjoy a friendship. And they do; Mary Kerrigan and Walter Macdonald play and probe and spar. Then the unanticipated happens: friendship deepens into love, and differences that were intriguing when they were just friends become ominous. She's irreverent; he's traditional. She's unfettered;...