A heavenly chorus praises God the Creator. Mefistofele scornfully declares that he can win the soul of Faust. His challenge is accepted by the Forces of Good.
The aged Dr. Faust and his pupil Wagner are watching the Easter celebrations in the main square in Frankfurt. Faust senses that they are being followed by a mysterious friar, about whom he senses something evil. Wagner dismisses his master's feelings of unease and as darkness falls they return to Faust's home
Faust is in his study, deep in contemplation. His thoughts are disturbed in dramatic fashion by the sudden appearance of the sinister friar, whom he now recognizes as a manifestation of the Devil (Mefistofele). Far from being terrified, Faust is intrigued and enters into a discussion with Mefistofele culminating in an agreement by which he will give his soul to the devil on his death in return for worldly bliss for the remainder of his life.
Restored to his youth, Faust has infatuated Margareta, an unsophisticated village girl. She is unable to resist his seductive charms and agrees to drug her mother with a sleeping draught and meet him for a night of passion. Meanwhile Mefistofele amuses himself with Martha, another of the village girls.
Mefistofele has carried Faust away to witness a Witches' Sabbath on the Brocken mountain. The devil mounts his throne and proclaims his contempt for the World and all its worthless inhabitants. As the orgy reaches its climax Faust sees a vision of Margareta, apparently in chains and with her throat cut. Mefistofele reassures him that the vision was a false illusion.
Faust's vision had been true. Margareta lies in a dismal cell, her mind in a state of confusion and despair. She has been imprisoned for poisoning her mother with the sleeping draught supplied by Faust and for drowning the baby she had borne him. Faust begs Mefistofele to help them escape together. They enter the cell and at first Margareta does not recognize her rescuers. Her joy at being reunited with Faust turns to horror when she sees Mefistofele and recognizes that he is the Devil. Refusing to succumb to further evil, Margareta begs for divine forgiveness. She collapses to the cell floor as the Celestial choir proclaims her redemption.
Mefistofele has now transported Faust back in time to Ancient Greece. Helen of Troy and her followers are enjoying the luxurious and exotic surroundings on the banks of a magnificent river. Faust, attired more splendidly than ever, is easily able to win the heart of the beautiful princess. In a passionate outpouring they declare their undying love and devotion to each other.
Back in his study Faust, once more an old man, reflects that neither in the world of reality or of illusion was he able to find the perfect experience he craved. He feels that the end of his life is close, but desperate for his final victory, Mefistofele urges him to embark on more exotic adventures. For a moment Faust hesitates, but suddenly seizing his Bible he cries out for God's forgiveness. Mefistofele has been thwarted; he disappears back into the ground as Faust dies and the Celestial choir once more sings of ultimate redemption.