Maisie Dobbs must unravel a case of wartime love and death—an investigation that leads her to a long-hidden affair between a young cartographer and a mysterious nurse.

August 1914. Michael Clifton is mapping the land he has just purchased in California's beautiful Santa Ynez Valley, certain that oil lies beneath its surface. But as the young cartographer prepares to return home to Boston, war is declared in Europe. Michael—the youngest son of an expatriate Englishman—puts duty first and sails for his father's native country to serve in the British army. Three years later, he is listed among those missing in action.

April 1932. London psychologist and investigator Maisie Dobbs is retained by Michael's parents, who have recently learned that their son's remains have been unearthed in France. They want Maisie to find the unnamed nurse whose love letters were among Michael's belongings—a quest that takes Maisie back to her own bittersweet wartime love. Her inquiries, and the stunning discovery that Michael Clifton was murdered in his trench, unleash a web of intrigue and violence that threatens to engulf the soldier's family and even Maisie herself. Over the course of her investigation, Maisie must cope with the approaching loss of her mentor, and her growing awareness that she is once again falling in love.