The action unfolds during the Hundred Years' War.
The little village of Domrémy. Young women are decorating a much-loved oak tree with garlands. Joan appears with her father Thibaut and Raymond, her betrothed. Thibaut is eager for the marriage to take place as soon as possible: in such dangerous times Joan should have a husband to protect her. The refusal of the girl, convinced that she has some other calling, enrages the father. He suspects that his daughter has made a pact with the powers of darkness, and so he rebukes her. The glow of a fire can be seen on the horizon and the alarm is heard. Peasants ruined by the English hasten in. The elderly Bertrand tells of what a desperate state the country is in: Orleans has been besieged by troops under the leadership of the unbeaten Salisbury. Unexpectedly for all, Joan announces that the troubles will soon be at an end, and she foretells the triumph of France. The people are amazed: "In these days, alas, the Lord creates no miracles!" "There are miracles..." exclaims Joan, "And a miracle has already occurred, the fearsome leader Salisbury has been reduced to dust!" No-one believes her. And yet a soldier who has arrived from Orleans confirms it: Salisbury lies dead. Having come to believe Joan, all pray to God. Left alone, the girl convinces herself that the time has come to act. She is gripped with a sense of nostalgia at being parted from her village and she hesitates. A chorus of angels can suddenly be heard. This inspires Joan to do battle.
At the Château de Chinon King Charles VII and his beloved, Agnès Sorel, are being entertained. Minstrels, dwarves, gypsies and jesters follow one another in a succession of songs, dances and amusements. The monarch orders the artistes be given food and drink and a golden chain each. Dunois the knight remarks that chains cannot be forged from words, that the treasury is empty and the troops are ready to desert. Agnès decides to donate her jewels to pay the wages and immediately goes to fetch her casket. The king admits to Dunois that it is possible to survive any unhappiness if one is loved by such a woman. "This is no time for love," objects Dunois, and he convinces the king to head the regiments. The king recalls that he is a knight and resolves on war.
The wounded knight Lauret hastens in with news of a battle lost and dies at the feet of his sovereign. Despairing, Charles decides to flee. Dunois spurns him and departs to die in battle. Returning, Agnès is amazed at the news but attempts to comfort her beloved.
Off-stage, fanfares can be heard: a miracle has occurred and the English have been defeated and routed. The Archbishop appears and confirms the news: at a critical point a maid appeared and seized victory from the hands of the enemy. The cries of the people and the pealing of bells can be heard. Joan appears accompanied by the knights. At her arrival, the king orders Dunois to take the position of monarch, himself hiding among the throng of courtiers. Joan, however, goes directly to the king. In response to his surprise, she admits that she saw him where "he was seen to none but God", and names the three prayers he said. All are stunned. "Who are you?" they ask her. She relates her story. The king entrusts his troops to Joan, and all delightedly welcome her.
Scene 1. Not far from the battlefield. the English and their allies – the Burgundians – have been defeated. Joan unarms the Burgundian knight Lionel. Raising her sword over him, in the moonlight she sees his face. Staggered by the youth's handsome features, Joan is unable to strike him down. Lionel, humbled by the girl's noble and generous behaviour, calls on her to follow him and leave behind her death-dealing sword. Joan is assailed by doubt. Dunois appears. Lionel throws himself at him and says that he is defecting to the French side. Dunois accepts his repentant enemy and relates that the battle is won and that the gates to the city of Reims have been opened to Charles VII, his coronation to take place at the cathedral there. Exhausted, Joan collapses into Dunois' arms; she has been wounded.
Scene 2. The square in front of the cathedral of Reims. A triumphant procession heads to the cathedral where Charles VII is to be crowned king. The people praise the maid and the king. Thibaut and Raymond appear in the crowd. Convinced that his daughter is in league with the Devil, Thibaut intends to restore her to God and "abandon the worthless adulation". Raymond entreats him not to kill the girl. The procession headed by the king leaves the cathedral. The king declares Joan to be their salvation and asks her to show her radiant and immortal face. Suddenly Thibaut appears before her and accuses his daughter of colluding with the forces of Hell. Joan remains silent, believing she has no right to defend herself: she has sinned and broken her vow by falling in love with Lionel. Dunois takes arms to defend her innocence. Just then, an almighty peal of thunder is heard. All step back from Joan. Again Joan's father demands an answer from her. There is another even more mighty peal of thunder. The Archbishop turns to Joan and asks her the same question – is she innocent? She makes no answer. There is yet more thunder, still mightier than before. In fear, all abandon Joan. Lionel offers her his protection, but with hatred in her voice Joan tells him that he is her worst enemy and she runs away. Lionel follows after her.
Scene 1. In the forest. Hiding from the people, Joan is unable to overcome her emotions: her soul is burning with the flames of passion. In torture she thinks fondly of Lionel and greets his unexpected appearance with a joyful exclamation. A moment of sheer bliss. Joan hears the voices of the angels: she has disregarded the behest of Heaven – she has allowed earthly love into her heart – and so cannot complete her holy mission. She must submit to her ill-fated destiny without complaint – redemption will be her reward. The English suddenly appear and capture Joan while Lionel, trying to protect her, is killed.
Scene 2. A square in Rouen. A funereal procession: Joan is being led to her execution. She asks for a crucifix. Surmounting her fears, the maid climbs onto the pyre. "The Heavens have opened up and suffering is at an end!" are her last words.