The young gods under the aegis of Zeus have toppled the ancient empire of Kronos and overpowered the Giants and Titans. Zeus also plans to wipe out the whole of mankind because of its imperfections. Prometheus defies his wishes and becomes the helper of mankind. Zeus plans to punish the rebel for his presumptuousness.
Zeus’ myrmidons urge the reluctant god Hephaistos, patron of the smiths, to chain the »villain« Prometheus to the rocks in far-off Scythia. The god who has endured his captivation in silence intones a great lament which is taken over by the chorus whose lament for Prometheus is intended to be audible throughout all countries, across all seas and in Hades. Prometheus relates how he saved mankind from destruction by teaching them how to master and interpret the world.
Io then rushes in screaming with pain.
She tells of her cruel fate and requests Prometheus to predict her destiny. He fulfils her demand in three speeches.
While the chorus reflects on Io’s fate, Prometheus intensifies his threat to destroy the reign of Zeus. The rock on which Prometheus is rearing up in his accusations is struck by lighting from Zeus and sinks into the depths of the Tartaros in a storm of ether.
 Werner Thomas in: Pipers Enzyklopädie des Musiktheaters, Vol. 4, Munich 1991, p.581 ff.
Image: Werner Schloske