Romanticized story of Louise de Bettignies (1880-1918), a French spy and heroin of the First World War. In October 1914, in occupied Roubaix, Geneviève de Vandeville manages to deliver mail in secret to the still free zone. She is soon contacted by the Intelligence Service who asks her to lead a team of spies. Responsible for delivering intelligence about German troops to the French and British, she enlists the help of Maria, a young girl who becomes her friend. One day, Maria and her lover Charles ask Geneviève to plan their escape into Holland. This mission will prove fatal for Geneviève. She is detected by the German counterespionage, arrested, and imprisoned in Brussels. She becomes sick and dies in prison before the war ends. Some time later, Maria and Charles pay their respects to the monument in effigy of Louise de Bettignies.