The principal characters in
Children of Heracles are
Eurystheus, the king of
Mycenae and a
tyrant who was responsible for Heracles's
labours; Iola, Heracles's old friend who provides protection to the children;
Demophon, the king of Athens, son of
Theseus, and an ally; and
Macaria, Heracles's daughter and
Alcmene, Heracles's elderly mother. Other characters include
Hyllus, Heracles's eldest son and the
herald Copreus. The play begins at the altar of
Zeus at
Marathon where Heracles's children, Iolaus and Alcmene take shelter. King Eurystheus is determined to kill the children, wary that they will want to avenge their father. Copreus, in the employ of Eurystheus, attempts to seize the children and Iolaus. Iolaus begs for help, and King Demophon arrives. He declares that Iolaus and Heracles's children are under his protection. With tensions rising
, Copreus threatens to return with an army. Demophon is prepared to protect the children even at the cost of fighting a war against Eurystheus, but after consulting with the
oracles, he learns that the Athenians will be victorious only if they sacrifice a
maiden of noble birth to the goddess
Persephone,
"They bid me to sacrifice a maiden to the daughter of Demeter, a maiden daughter of a noble father, to rout the enemy and save the city." Reluctant, Demophon tells Iolaus that as much as he would like to help, he will not sacrifice his own daughter or compel any of the Athenians to do so. Iolaus, realizing that he and the children will have to leave Athens and seek refuge elsewhere, despairs. Known as the Maiden in the play, Macaria hears the oracle's announcement. Realizing her family's predicament, she courageously offers herself as the sacrificial victim, refusing a lottery among other girls. She bids farewell to her siblings and to a grieving Iolaus, "
Farewell, old man, farewell! Please train up [575] these boys to be such men as yourself, wise for every occasion, not more wise than that: that will suffice. With all your zeal try to save them from death. We are your children, we have been raised by your hands. You see that I am offering my young womanhood [580] and about to die in their place." Macaria is led away to be sacrificed. Hyllus arrives with reinforcements and Iolaus insists on joining the battle. During the fight, Iolaus miraculously regains his youth and captures Eurystheus. Alcmene furiously orders that Eurystheus be executed immediately for the grief he has caused them, though such an execution is against Athenian law. Eurystheus accepts his fate and tells them a prophecy of how his spirit will protect the city from the descendants of Heracles's children if they slay and bury him,
"And you shall have a double profit from me: by dying I shall bring benefit to you and harm to the Heraclids." Eurystheus is then escorted away to be executed and the play ends. == Reception ==