The German occupation of Paris during World War II was a time of shifting and uncertain alliances, and life for Parisians required a bit of careful attention. Suzanne Lang talks with Aurelie Thiele, author of the historical novel, The Paris Understudy, a sweeping tale of the Paris Opera world, two rival opera singers, their struggle for success amidst Hitler and the Nazis, and their plight to save others victimized by them.