While attempting to help a woman in distress, World War I battlefield nurse Bess Crawford learns a bitter truth, that no good deed goes unpunished.

Returning to her London flat from the front lines in France for a well-earned Christmas leave, Bess Crawford comes upon a bruised and shivering woman huddled in the doorway. Propelled by pity, Bess takes her in. Yet despite the ill effects of a concussion suffered during a quarrel with her husband that erupted into violence, the woman decides to return home, and asks Bess to travel with her to Sussex.

At Vixen Hill, Bess discovers a family in mourning for an elder son who has died of war wounds, and a husband tormented by jealousy and his own guilty conscience. But when a troubled houseguest meets an untimely death, Bess finds herself the prime suspect, and on the trail of a vicious killer that leads back to war-torn France toward a startling revelation that will place her life in dire jeopardy.