In 1932 the remains of American-born cartographer Michael Clifton are recovered from a former battlefield in France. His parents ask Maisie to identify the nurse who wrote the love letters found with him, but evidence on the body suggests that Michael was murdered rather than killed during combat.
Maps, property interests and wartime correspondence lead Maisie through the private history of a young man who volunteered for British service in 1914. The case reawakens memories of her own wartime love and places the Clifton family in danger, while the failing health of Maurice Blanche forces Maisie to consider how much of her life has been shaped by the dead.