The play is set between 1429 and 1431, with an epilogue set in 1456. During this time, the 100 Years War was raging between England and France, and English forces had occupied a number of French cities and towns. The play begins with Joan asking a French nobleman, Robert de Baudricourt, to provide her with armor, a horse, and soldiers. Joan is an adolescent girl from a small country village, but she has had visions of saints telling her that it is her destiny to lead French forces to victory and ensure that the Dauphin (heir to the throne) is officially crowned as King. Robert is hesitant to support Joan, but he gives in when he sees that she is capable of inspiring men to fight for her.
Joan travels to Chinon, where the Dauphin has set up an informal court. Despite an attempt to trick her, she easily identifies the Dauphin, which further encourages others to see her as guided by God. Joan persuades the Dauphin that she is going to free the city of Orleans (held under siege by English forces) and have him crowned at Rheims Cathedral. Leading troops, Joan goes to Orleans, where the French forces are frustrated. They need the winds to change so that they can sail upriver and attack the English from behind. Joan prays, and the wind immediately changes, allowing the French forces to win a triumphant victory.
The French victory at Orleans changes the tide of the war, which worries English leaders. Earlier in the war, the English had formed an alliance with the Burgundians, a French faction who opposed the royal house to which Charles belonged. Warwick, an English nobleman, meets with Cauchon, a Burgundian Bishop. Both men agree that Joan is dangerous and must be eliminated. Meanwhile, Charles has been crowned at Rheims Cathedral. Joan is worried because she seems to be becoming unpopular, and several people accuse her of being proud, stubborn, and reckless. With Charles crowned, Joan wants to lead forces to try to take back Paris, but no one supports this plan. Nonetheless, Joan insists that she has to follow God's orders.
The action of the play then jumps ahead 2 years, to 1431. In the interim, Joan has been captured by Burgundian forces and sold to the English. She is now on trial on charges of heresy, with a number of Church officials questioning her. Undaunted, Joan defends her decision to wear men's clothes, and she insists that her voices are truly the voices of divine messengers. She only wavers when she is threatened with execution, at which time Joan signs a confession and recantation. However, she is horrified to realize that even though her life will be spared, she is still going to be imprisoned for life. Faced with this fate, Joan tears up her confession. She is immediately taken out to be executed. Other characters report that she showed great strength and courage during her painful execution.
The epilogue to the play is set 25 years later. An inquiry has been held into Joan's trial, and the charges have been reversed: Joan is now declared innocent. Her spirit appears in a vision to Charles, who is now successfully ruling as a strong French king. The pair are joined by many other characters, showing that Joan has now been vindicated and that her enemies have been proven wrong. Eventually, a man dressed in 1920s-style clothing appears and announces that Joan has been declared a saint. Excited by all of the seeming praise and recognition, Joan suggests that maybe she should return to life. However, all of her seeming allies immediately abandon her, making excuses for why this is not a good idea. At the end of the play, Joan is left alone, wondering when the world will be ready to fully embrace her.
