For Iris, each visit to her mother in St Mabon’s Cove, Cornwall has been the same—a serene escape from the city. But today, as she breaths in the salt air on the doorstep of her beloved childhood home, a heavy weight of anticipation settles over her. Iris knows she’s adopted, but any questions about where she came from have always been shut down by her parents, who can’t bear to revisit the past. Now, Iris can’t stop thinking about what she’s read on the official paperwork: BABY GIRL, FRANCE, 1939 – the year war was declared with Nazi Germany.

1997. Amy Novak has lost the two great loves in her life: her husband, Michael, and her first love, music. With the first anniversary of Michael's death approaching, Amy buries herself in her job as an archivist. And when a newly declassified file lands on her desk, she is astonished to uncover proof that Agent 'Colette' existed—a name spoken only in whispers; an identity so secret that it has never been verified.

Londoner Madeleine Grant is studying at the Sorbonne in Paris when she marries charismatic French journalist Giles Martin. As they raise their son, Olivier, they hold on to a tenuous promise for the future. Until the thunder of war sets off alarms in France. Staying behind to join the resistance, Giles sends Madeleine and Olivier to the relative safety of England, where Madeleine secures a job teaching French at a secondary school. Yet nowhere is safe. After a devastating twist of fate resulting in the loss of her son, Madeleine accepts a request from the ministry to aid in the war effort.

France, 1942. At the end of the day, the schoolteacher releases her pupils. She checks they have their identity passes and warns them not to stop until the German guards have let them through the barrier that separates occupied France from Free France. As the little ones fly across the border and into their mothers' arms, she breathes a sigh of relief. No one is safe now. Not even the children.

Germany, 1945. As the ground shakes and the air raid sirens wail, Katja holds her tiny baby to her chest. She pictures Karl’s handsome face and kind blue eyes, her breath catching at the thought of him heading back to the front. She must never tell anyone about the letters she delivered for him or the other secret she is hiding....

Paris, 1943. German soldiers drag me out onto the cobbled street and push me toward the waiting truck. I force myself to face forward as tears stream down my cheeks. If I look back, they’ll know. I can’t let them find my baby girl....

I sent 19-year-old Phyllis, my youngest recruit, into a city crawling with enemy soldiers. And this beautiful house on a tree-lined street, the headquarters of cold-hearted German soldiers, was the last place she was seen. I trail my fingers along the gilded furniture and see the light dance off the glittering chandeliers. On the top floor, I find the dates inscribed by beaten prisoners, and I know my girl was shown no mercy.

1940. Cora Mayhew came to Paris to search for her birth mother and stayed to work for the resistance movement. When Cora's train is struck by Nazi bombs, the only thoughts on her mind as she staggers from the wreckage are to escape to return to her family, and to post the heart-wrenching letter clutched in her hand. Then a German soldier finds and saves Cora. Max Heller is nothing like she would have expected: kind, good-humoured and selfless. Cora can't help falling in love with him as he helps to plot her escape.

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.

Sophie Dix fled Stuttgart with her brother as the Nazi regime gained power in Germany. Now, with her brother gone and her adopted home city of Paris conquered by the Reich, Sophie reluctantly accepts a position restoring damaged art at the Jeu de Paume museum under the supervision of the ERR—a German art commission using the museum as a repository for art they’ve looted from Jewish families.

All her life, Zofia has found comfort in two things during times of hardship: books and her best friend, Janina. But no one could have imagined the horrors of the Nazi occupation in Warsaw. As the bombs rain down and Hitler’s forces loot and destroy the city, Zofia finds that now books are also in need of saving. With the death count rising and persecution intensifying, Zofia jumps to action to save her friend and salvage whatever books she can from the wreckage, hiding them away, and even starting a clandestine book club.

1940 - Stasia always found comfort in the idyllic French countryside where she spent her childhood summers, roaming the gardens of an old chateau and finding inspiration for fairy tales full of bravery and adventure. But these days are much darker, and with Nazis storming across Europe, she soon finds herself one of the most hunted agents of the Resistance. The only safe haven she can think of is Chateau de Montissaire. But she’s about to discover that it just may be the center of her biggest mission yet.

London, 1933. At first glance, Austrian opera singer Elsa Mayer-Braun has little in common with the young English typist she encounters on tour. Yet she and Hattie Featherstone forge an instant connection—and strike a dangerous alliance. Using their friendship as a cover, they form a secret society with a daring goal: to rescue as many Jews as possible from Nazi persecution. Though the war’s outbreak threatens Elsa and Hattie’s network, their efforts attract the covert attention of the British government, offering more opportunities to thwart the Germans.

Paris, 1939: Young and ambitious Odile Souchet seems to have the perfect life with her handsome police officer beau and a dream job at the American Library in Paris. When the Nazis march into the city, Odile stands to lose everything she holds dear, including her beloved library. Together with her fellow librarians, Odile joins the Resistance with the best weapons she has: books.

Elisabetta, Marco, and Sandro grow up as the best of friends despite their differences. Elisabetta is a feisty beauty who dreams of becoming a novelist; Marco the brash and athletic son in a family of professional cyclists; and Sandro a Jewish mathematics prodigy, kind-hearted and thoughtful, the son of a lawyer and a doctor. Their friendship blossoms to love, with both Sandro and Marco hoping to win Elisabetta's heart.