A rustic village
Giselle, a weak-hearted young girl who is adored by her native villagers, lives with her watchful mother, Berthe. Hilarion, the village gamekeeper, is desperately in love with Giselle. Prince Albrecht, a nobleman who is already engaged to a noblewoman named Bathilde, is bored and lonely with his everyday existence. Captivated by Giselle's frail beauty and innocence, Albrecht disguises himself as a peasant named Loys. After purchasing the cottage adjacent to Berthe's, he proceeds to shower Giselle with his affections.
Hilarion, filled with suspicion and jealousy, becomes enraged when Giselle falls madly in love with Albrecht and believes that they are engaged.
Berthe has a vision that her daughter will one day become a Wili, a jilted maiden who dies before her wedding night. The Wilis emerge between midnight and dawn to vengefully trap any man who enters their domain by forcing him to dance to his death.
Hilarion exposes Albrecht's disguise and proclaims that he is already betrothed to Bathilde. Overwhelmingly distraught and horrified, Giselle dies of a broken heart.
Act II - A forest clearing
Hilarion is discovered just before midnight keeping vigil by Giselle's tomb. As midnight approaches, the Wilis appear with their leader, Queen Myrta. This is the night Giselle is to be initiated as a Wili.
Albrecht, laden with feelings of guilt and remorse, visits Giselle's grave. He sees a vision of Giselle and follows it into the forest. At this point, Myrta discovers Hilarion in the forest and orders the Wilis to dance around him until he dies from exhaustion. She then discovers Albrecht and demands that he share the same fate as Hilarion but is unable to permeate the invisible bond of love that Giselle has for him.
At dawn, when the Wilis lose their power and must retreat to their dwelling place, Albrecht is saved and Giselle forgives him. Giselle returns with the Wilis and recognizes that now she will be one of them for the rest of time.