During the Nazi occupation of Paris the company of the Montmatre Theatre works on a new play. Lucas Steiner, director of the theatre and a German jew, hides in the cellar while his wife Marion officially runs the theatre. She hires Bernard Granger as the new leading man. The two fall in love but resist temptation out of respect to her husband. Soon Marion has to choose between loyalty to her husband and to her countrymen. Both possobilities are acted out on stage during the presentation of the play. After the premiere Lucas decides to join the Resisitance.