In occupied Belgium during World War II, the chateau where Nicole de Malvines [Maria Schell] de Malvines and her mother live is partly requisitioned by German forces, bringing Colonel Günther von Hohensee [Marius Goring], a ruthlessly efficient Prussian officer, into their daily lives. Nicole, proud and outspoken after losing several male relatives to the war, openly resents the occupiers and makes her contempt clear to the imposing officer. Their tension softens, however, when they discover a shared passion for music, especially the piano, and Günther begins to coach Nicole, weaving a fragile thread of affection between them.
As their private moments grow more intimate, they travel to Brussels to attend the opera, mindful of how easily their discreet society could collapse if anyone suspects their bond. The romance becomes a dangerous secret, sharpened by the looming threat of discovery and the moral complexity of the war around them. At the same time, Nicole’s cousin Phillipe de Malvines [John Bailey] leads a Belgian Resistance cell that aims to seize documents from von Hohensee to pass on to their cause, underscoring that non-cooperation is not an option.
The relationship faces inevitable strain as the couple realizes the odds against them. A sympathetic observer and former lover of the opera world, Lotte Schönberg [Lucie Mannheim], urges Günther to confess his love and to seize the time they have, reminding him that there is > "so little time." Günther acknowledges his love for Nicole and believes she loves him too, yet he believes there is too much standing in the way of a future together and contemplates a transfer back to frontline duties.
Tensions come to a head when Günther humiliates one of Nicole’s friends, Gerard [Oscar Quitak], during a heated moment, driving a temporary rift between the lovers. WhenNicole learns that he is leaving soon, she pleads with him not to go, and eventually he cannot resist her and they renew their vow to stay together despite the danger. Their fragile happiness is swept away as betrayals unfold, and both must confront the consequences of their choices.
The turning point arrives when Nicole is found to have taken documents from Günther’s desk and returns from delivering them to Phillipe. In the tense confrontation that follows, she is inadvertently shot by Phillipe during an attempt to kill Günther and dies in his arms. Unable to reconcile the loss and facing imminent Gestapo arrest, Günther takes his own life, overwhelmed by grief and the impossibility of their future.
