Shortly before the outbreak of World War I, a temperamental young woman quarrels with her fiancé, breaks off her engagement, and leaves America for France. Four years later, at the time when the American armed forces are battling the Germans at Chateau-Thierry, the woman, who is still estranged from her sweetheart, becomes the unwitting accomplice of German secret agents. In an attempt to manipulate international borders, the agents move near the woman's house, and for the moment, her sweetheart is powerless to come to her aid.—AFI