Two brothers vie to rule in an ancient city. The elder, Atreus, was king before his wife Aerope betrayed him, taking the younger brother Thyestes as her lover, helping him to steal the golden ram. This golden ram has magical powers. You must possess it to be king. Thyestes is a liberal, generous ruler and Aerope sees herself as a divinely inspired liberator of her people, not as a criminal adulteress.
But Atreus does not agree and has been at work gathering support. In a bloodless coup, he sends Thyestes and Aerope into exile in the forest. He reclaims the throne and locks the ram into a chest.
After ten years the people have had enough of the oppressive Atreus. They celebrate the return of Thyestes and Aerope and their two boys, Pelops and Plianthus. Atreus orders a feast prepared in the traditional manner; men only, each at a separate table. He forces two of his desperate courtiers to murder the little boys and cook them into a stew. He tricks Thyestes into eating the flesh of his own children, a crime punishable by permanent exile. Torn apart by horror and grief, Thyestes calls down a curse on the house of Atreus. Aerope kills herself before Atreus can execute her. Atreus, alone, settles onto his throne only to be confronted by the Sun, who, looking down and seeing the unspeakable crimes, refuses to shine and retreats, plunging the Earth into darkness, and changing forever the relationship between the human race and the sun.