The true story of Violette Szabo, a heroine of the Second World War for her espionage activities on behalf of the British government. Born Violette Bushell (Virginia McKenna) to a French mother and an English father, she chances to meet Etienne Szabo (Alain Saury), a French officer, whom she later marries. They have a child, Tania, but Etienne is fatally wounded in the Battle of El Alamein. Violette is already contributing to the war effort at home, but soon discovers that her bi-lingual skills make her a potentially valuable member of England's Special Operations Executive, the country's wartime overseas espionage unit. She agrees to join and, after extensive training, is sent into France in the spring of 1944, on a mission to salvage a resistance unit in Rouen area. Szabo completes that mission successfully and returns home, intending to resume her life as a mother raising her daughter -- but she is offered a second mission in France, immediately after the Normandy landings, and accepts, with tragic consequences.