1944. As darkness descends over Europe, nineteen-year-old Hedy chooses hope in the face of the evil that grips the continent and stalks the streets of her quiet Swiss hometown.

One night in the forest, with only the light of the moon to guide her, Hedy finds a wounded American airman. Second Lieutenant Samuel Reardon was dropping supplies to the French resistance when his plane crashed. Despite the grave danger it will bring her whole family to harbour an Allied soldier, Hedy can't leave Samuel injured and alone, so she hides him in her father's mountain hut.

Risking everything, Hedy cares for Samuel in secret. And, as burgeoning feelings grow between them, their dangerous resistance work leaves them facing a decision that could tear them apart forever. . .

2018, America. Nineteen-year-old Gina looks at her grandmother's wrinkled hands. They tell the story of Hedy's whole life. Since Gina's mother died, Mamie Hedy is all she has - and Gina can't help wonder how much time they have left together. But then her grandmother reveals a shocking secret that takes them all the way back to her childhood home in the Swiss mountains . . .