1932. After the Great War took both her beloved brother and her fiancé, Violet Speedwell has become a "surplus woman," one of a generation doomed to a life of spinsterhood after the war killed so many young men. Yet Violet cannot reconcile herself to a life spent caring for her grieving, embittered mother. After countless meals of boiled eggs and dry toast, she saves enough to move out of her mother's place and into the town of Winchester, home to one of England's grandest cathedrals.

Catherine the Great was a woman of notorious passion and imperial ambition. Prince Potemkin was the love of her life and her co-ruler. Together they seized Ukraine and Crimea, territories that define the Russian sphere of influence to this day. Their affair was so tumultuous that they negotiated an arrangement to share power, leaving each of them free to take younger lovers. But these “twin souls” never stopped loving each other.

Twenty-five years after the end of the war, Noah Ainsworth is still preoccupied with those perilous, exhilarating years as a British SOE operative in France. A head injury sustained on his final operation has caused frustrating gaps in his memory—in particular about the agent who saved his life during that mission gone wrong, whose real name he never knew, nor whether she even survived the war.

It is 1936, and Nancy Wake is an intrepid Australian expat living in Paris who has bluffed her way into a reporting job for Hearst newspaper when she meets the wealthy French industrialist Henri Fiocca. No sooner does Henri sweep Nancy off her feet and convince her to become Mrs. Fiocca than the Germans invade France and she takes yet another name: a code name. As Lucienne Carlier, Nancy smuggles people and documents across the border and earns a new nickname from the Gestapo for her remarkable ability to evade capture: The White Mouse.

London, 1962: The world is teetering on the brink of nuclear war but life must go on. Celia Duchesne longs for a career, but with no means or qualifications, passes her time working at a dusty bookshop. The day a handsome American enters the shop, she thinks she might have found her way out of the monotony. Just as the excitement of a budding relationship engulfs her, a devastating secret draws her into the murky world of espionage.