Tending to the soldiers in the trenches of France during the First World War, battlefield nurse Bess Crawford can't help but notice the photo of a young pilot's wife every time she tends to him. But then at the railway station, in a mob of troops leaving for the front, Bess glimpses a familiar face—the pilot's wife, with another man. Later, back in France, Bess sees a newspaper with a drawing of the woman's face on the front page. She'd been murdered—the very day Bess saw her. Bess is soon on the search for a devious and very dangerous killer—a search that will put her own life in jeopardy.