The women of the chorus lie at rest in a peaceful green meadow. Phorkyas enters and reports to them about the wondrous things that have just taken place in the secluded bower where the lovers Faust and Helen have hidden themselves. A son, Euphorion, has been born to them. The lad is beautiful, alert, energetic, artistic. Already he is able to talk and move about freely. A strange aura surrounds his head and sweet music emanates from the cave around him.
Helen, Faust, and Euphorion come out. The boy promises that his existence will make their love more intense. They express their tender affection for each other. Suddenly Euphorion is filled with a wild desire to fling off all earthly shackles and soar high into the heavens. He is unable to restrain his passion and begins to pursue the maidens of the chorus. He embraces one, but the girl vanishes in a burst of flame.
Next Euphorion tries to climb a tall cliff in an effort to reach the greatest possible heights and survey the entire world. He does not heed the warnings of the chorus or his parents that such a rash attempt to grasp the ultimate so early in life will only result in his destruction. Danger, he replies, is a necessary and exhilarating part of life. Euphorion reaches the top of the cliff and hurls himself off, in an ecstasy of Romantic enthusiasm. For a moment he remains suspended in air, then falls to his death. His body disappears, but his clothing and lyre remain on the ground.
Euphorion's parents and the chorus lament his untimely end. The boy's voice is heard calling his mother to join him. Helen sadly bids Faust farewell, saying that happiness and beauty can never permanently be combined. She vanishes, leaving her veil behind.
Phorkyas tells Faust to keep the garment as a memento and inspiration. The heartbroken Faust is carried off in a cloud. Phorkyas reveals herself to be Mephisto in disguise and predicts that he will soon meet Faust again.
Euphorion is patterned after the English poet Byron, whose work blended Classic and Romantic themes, and whose temperament was unrestrained and adventurous in the "faustian" sense — ever striving to attain new experiences and greater heights of understanding. He was much admired by Goethe. The characterization also bears a similarity to the Boy-Charioteer of Act I. Euphorion's passionate aspirations and early death are meant to show the doom caused by excessive enthusiasm and extremes of violence and rebelliousness; in short, the inability to adjust to the requirements of real life. His death and Helen's disappearance convey the message that the two ideals, Romanticism and the Classical heritage, are integral parts of life, but are not in themselves sufficient for one to live by. The tangible remains left behind, the lyre and the veil, are reminders that for proper adjustment one must retain his belief in these ideals, but something more is required also. The final lyrics of the chorus assert the immortality of poetry, and affirm the value of life and creativity. They express Goethe's conception of the universe as a fluid whole which embraces all aspects of being.