While Adam, Eve, Abel, Zillah, and Adah pray to God, Cain stands sullenly by and complains that he has nothing to pray for because he had lost immortality when Eve ate the fruit from the tree of knowledge. He cannot understand why, if knowledge and life are good, his mother’s deed has been deemed a deadly sin. Abel, Adah, and Zillah urge him to cast off his melancholy and join them in tending the fields. Alone, Cain deplores his worldly toil. Tired of the repetitious replies to all his questions, replies that refuse to challenge God’s will, he is no longer sure that God is good.

At the conception of this thought, Lucifer appears to explain that Cain’s mortality is only a bodily limit. He will live forever even after death. Cain, driven by instinct to cling to life, at the same time despises it. Lucifer admits that he also is unhappy in spite of his immortality, which is a cursed thing in his fallen state. He launches into a bitter tirade against God, whom he describes as a tyrant sitting alone in his misery, creating new worlds because his eternity is otherwise expressionless and boring to him. Lucifer exults that his own condition is at least shared by others. These words echo Cain’s own beliefs about the universe. Long has he pitied his relatives for toiling so hard for sustenance, as God had decreed when he banished Adam and Eve from the Garden of Eden.

Lucifer confesses that the beguiling snake had not been a disguise for himself; the snake was merely a snake. He predicts, however, that later generations of humanity will array the fall of Adam and Eve in a cloak of fable. Cain then asks his mentor to reveal the nature of death, which holds great terrors for Cain. Lucifer promises to teach Cain true knowledge if Cain will worship him. Cain, however, having refused to worship even God, will not worship any being. His refusal is, according to Lucifer, in itself a form of worship.

Adah asks Cain to leave with her, but Cain claims that he must stay with Lucifer, who speaks like a god. Adah reminds Cain that the lying serpent, too, had spoken so. Lucifer insists that the serpent had spoken truly when it had promised knowledge from the fruit of the forbidden tree; humanity’s grief lies not in the serpent’s so-called lie but in humanity’s knowledge of evil. Lucifer says he will take Cain with him for an hour, time enough to show him the whole of life and death.

Traveling with Lucifer through the air, Cain, watching with ecstasy the beauty around him, insists upon viewing the mystery of death, which is uppermost in his mind. The travelers come at last to a place where no stars glitter, and all is dark and dreadful. As they enter Hades, Cain again voices his hatred of death, the end of all living things.

In the underworld, Cain sees beautiful and mighty shapes that, Lucifer explains, had inhabited the world and died by chaotic destruction in an age before Adam was created. When Lucifer taunts Cain with his inferiority compared to those other beings of an earlier age, Cain declares himself ready to stay in Hades forever. Lucifer confesses, however, that he has no power to allow anyone to remain in Hades. When he points out to Cain that the spirits of the former inhabitants of the earth had enjoyed a beautiful world, Cain says that Earth is still beautiful. His complaint is against human toil for what the earth bears, human failure...