The Austrian Jules and the French writer Jim get to know each other on Montmatre. Together they spend a holilday in Greece and become fascinated by the smile of an antique statue. Back in Paris they discover the same smile on a girl's face, Catherine. Both fall in love with the girl and the three become inseparable friends. Eventually Jules confesses his love for Catherine and although Jim is infatuated himself he has no objections. Jules and Catherine marry and have child. When they all reunited after the First World War Catherine falls in love with Jim. Despite their deep friendship their ménage-à -trois is about to apart. Catherine's undecisiveness to choose one of the men leads their friendship to a tragic end.