ACT 1
During Revolutionary times, the young and timid Blanche, daughter of the Marquis de la Force, resolves to take the veil without notice. Before she enters the convent of the Compiegne Carmelites, the Prioress tries to unveil her real reasons, reminding her that the convent cannot be a place of hiding, but should be protected by its members. Blanche’s resolve survives and the Prioress gives her blessing.
As she arrives, Blanche meets the young Sister Constance, a joyful and fun-loving girl, who predicts they will both die at young age, and on the same day. Shortly after, the Prioress dies in an anguishing agony that chocks Blanche profoundly. As she blesses her new pupil, the Prioress consigns Blanche to Mother Marie’s care.
ACT 2
The new Prioress warns the convent against upcoming adversity, encouraging them to stay strong and humble. Meanwhile, Blanche’s brother, the Chevalier de la Force, arrives, begging his sister to flee the danger of the Terror with him. Blanche restates her desire to stay, and die if need be.
While the Father Confessor announces he’s been forced into hiding, the Prioress warns the sisters against pride and the temptation of martyrdom, arguing only God can decide their fate. Timely words as an angry crowd enters the convent to expulse the nuns.
ACT 3
In the absence of the Prioress, Mother Marie proposes that the nuns take a vow of martyrdom, and submits this proposition to a secret vote. Blanche’s dissent renders the vote invalid, but Constance claims that it was actually she that voted against the vow, and that she is now reconsidering. Terrified, Blanche flees.
Mother Marie finds Blanche in her former house, traumatized by the death of her father. She declares that Blanche may have saved her life but not her soul. Shortly after, Blanche hears the Carmelites have been arrested.
Condemned to death, the sisters walk to the scaffold, carried by the sound of a beautiful Salve Regina. Suddenly, Blanche rises from the crowd, peaceful at last, to join Constance in this last ordeal.