Joining the elite Bletchley Park codebreaking team during World War II, three women from very different walks of life uncover a spy's dangerous agenda years later against the backdrop of the royal wedding of Elizabeth and Philip.

A journalist in 2019 London interviews a World War II-era model to learn the story of the woman's best friendship with a Royal Air Force pilot's wife, who was catapulted by the Blitz into a web of intrigue and secrets.

Unable to confront the challenges in her own life, Cara Hargraves immerses herself in work for her antiques-dealer boss, uncovering relics from the life of World War II British "Gunner Girl" Louise Keene and her complicated relationship with a man named Paul.

Brought to Paris by an Austrian aristocrat who disappears when World War II breaks out, Ada, a talented dressmaker, survives by working for Nazi wives and is forced to endure the consequences of her choices years later.

Returning to the tranquil estate of her childhood after suffering the losses of her husband and young child, Julia reunites with the estate's heir, with whom she discovers an old diary and learns the story of an ancestor's heartbreak on the eve of World War II.