From New York Times bestselling author Marie Benedict—she'll have to choose: her country or her sisters? Between the World Wars, the six Mitford sisters dominate the English political, literary, and social scenes. Though they've weathered scandals before, the family falls into disarray when Diana divorces her husband to marry a fascist leader and Unity follows her sister's lead, inciting rumors that she's become Hitler's own mistress. Novelist Nancy Mitford is the only member of her family to keep in touch with Diana and Unity after their desertion, so it falls to her to act when her sisters become spies for the Nazi party. Probing the torrid political climate of World War II and the ways that sensible people can be sucked into radical action, The Mitford Affair follows Nancy's valiant efforts to end the war and the cost of placing loyalty to her country above loyalty to her family.