Act 1
Scene: A vast, lavish semi-circular hall in Barbe-bleue's castle

Ariane is destined to be Barbe-bleue's sixth wife. As she and her nurse arrive at Barbe-bleue's castle, they are greeted (offstage) by a chorus of peasants clamouring for Barbe-bleue's death because they believe he has murdered his former wives. Ariane is convinced they are still alive. She declares: Il m'aime, je suis belle, et j'aurai son secret. D'abord il faut désobéir: c'est le premier devoir quand l'ordre est menaçant et ne s'explique pas. – Les autres ont eu tort et les voilà perdues pour avoir hésité. ("He loves me, I am beautiful, and I will discover his secret. First one must disobey: it's the primal duty when an order is menacing and unexplained. – The others were mistaken and now they are lost because they hesitated.")

Barbe-bleue has given her seven keys to his treasure chambers: the six silver ones she is permitted to use, but the seventh, golden key is forbidden. Ariane says this is the only key which matters and goes to look for the seventh door while her nurse opens the others. The nurse turns the lock in the first door and a cascade of jewels and other treasures spills out. The second door reveals a "shower of sapphires"; the third, a "deluge of pearls"; the fourth, a "waterfall of emeralds"; the fifth, "a tragic torrent of rubies". Ariane is unimpressed by the gems, although the contents of the sixth, "avalanches of gigantic diamonds", elicit a cry of wonder from her ("O mes clairs diamants!"). The sixth door also reveals the vault containing the seventh to Ariane. Ignoring her nurse's warning, she turns the golden key in the lock. At first it reveals nothing but darkness, then "the stifled sounds of far away singing rise from the bowels of the earth and spread across the hall." It is the voices of Barbe-bleue's other wives singing a folk song "Les cinq filles d'Orlamonde" ("The five maids of Orlamonde"). The nurse is terrified and tries to shut the door again but she is powerless to move it as the voices draw nearer. At the last words of the song, Barbe-bleue enters the hall. He accuses Ariane: Vous aussi... ("You too..."). She replies, Moi surtout ("Me above all"). He tells her that through her disobedience she is abandoning the happiness he has offered her. She tells him, "The happiness I want cannot thrive in the shadows." Barbe-bleue grabs her by the arm and tries to drag her towards the seventh door. As he does so, the furious peasants smash the windows and break into the hall to confront Barbe-bleue, who draws his sword in defence. But Ariane calmly turns to the crowd and asks them "What do you want? – He has done me no harm" before closing the door on them.

Act 2
Scene: A vast, underground hall, at first shrouded in almost complete darkness

The seventh door has shut behind Ariane and the nurse. They explore the darkness with the aid of a lamp. Ariane is not afraid and believes Barbe-bleue will free them of his own accord: Il est blessé, il est vaincu, mais il l'ignore encore... ("He is wounded, he is defeated, but he doesn't know it yet..."). She finds the other wives hiding in the darkness, dressed in rags and terrified, but alive. She embraces them and says she has come to free them. She asks them if they have tried to escape. One wife (Sélysette) replies: On ne pourrait pas fuir; car tout est bien fermé; et puis c'est défendu ("We couldn't; everything is barred and bolted; besides, it is forbidden.") She asks their names and they give them, except for Alladine who is a foreigner and unable to speak. Drops of water from the vault extinguish Ariane's lamp and they are plunged into darkness. But Ariane thinks she can make out a faint source of light and gropes towards it. She finds it is a stained-glass window covered in grime. Taking a stone, she smashes the panes one by one and is dazzled by the light flooding in. The wives follow her. They can hear the sound of the sea, wind in the trees and the singing of birds. They gaze on a green country landscape as a village clock strikes midday. Ariane tells them not to be afraid but to follow the stone steps which lead down into the outside world.

Act 3
Scene: The same as Act 1

The castle's magic defences have prevented the wives from escaping and they find themselves in the hall, but they are happy as long as they are with Ariane. Barbe-bleue is nowhere to be seen. Ariane is certain they will soon be liberated. She helps the other wives to decorate themselves with the jewels from the six doors. The nurse enters and tells them Barbe-bleue is on his way. They look through the windows only to see Barbe-bleue's carriage ambushed by rebel peasants. Barbe-bleue's bodyguard is cut down and he is badly beaten. Ariane pleads with them not to kill him but they cannot hear. The peasants break down the castle door and enter with Barbe-bleue roped up. They fall silent at the sight of his wives and willingly turn over their captive to Ariane so she can take "vengeance". She thanks them and persuades them to leave the castle. The wives delicately care for the wounded Barbe-bleue before Ariane cuts his bonds with a dagger. Barbe-bleue is free and silently gazes at Ariane. She bids him "Farewell". He makes a feeble attempt to stop her then relents. Ariane asks the other wives if they are going to follow her: La forêt et la mer nous appellent de loin et l'aurore se penche aux voûtes de l'azur, pour nous montrer un monde inondé d'espérance... ("The forest and the sea are beckoning from afar and dawn is spreading over the azure heavens and will reveal a world filled with hope..."). None of them accepts the offer and Ariane leaves alone with her nurse. The wives gaze at each other, then at Barbe-bleue, who slowly lifts up his head.