"Juno, wife of Jove (Jupiter) is jealous of Alcmene, mother of Hercules by Jove, and has been persecuting Hercules by imposing labours on him, through her intermediary, the tyrant Eurystheus. The final labour, which Hercules has just completed, was the bringing up of Cereberus, the three-headed watchdog of the Underworld, up to the world above. To do this, Hercules has achieved the astonishing feat, never before accomplished, of returning from the realm of Death. Juno has now decided that sine labours cannot break Hercules, she will turn his own strength against him, by driving him mad when he returns to his home town of Thebes. In his madness, he will commit atrocities that will preclude his ascension into Heaven, which Juno is determined to prevent. "