January 1920. 350000 French soldiers remain missing in action. Major Dellaplane tirelessly matches the dead and the wounded with families' descriptions. Honor and ethics drive him; he hates the idea of "the unknown soldier." Into his sector looking for her husband comes a haughty politically connected Parisian Madame Irène de Courtil. Brusquely Dellaplane offers her 1/350000th of his time but as their paths cross and she sees his courage and resolve feelings change. After he finds a surprising connection between her missing husband and a local teacher Irène makes Dellaplane an offer. This man of action hesitates: has he missed his only chance?