In the tragedy, Iolaus, Heracles' old comrade, and Heracles' children, Macaria and her brothers and sisters have hidden from Eurystheus in Athens, ruled by King Demophon; as the first scene makes clear, they expect that the blood relationship of the kings with Heracles and their father's past indebtedness to Theseus will finally provide them sanctuary. As Eurystheus prepares to attack, an oracle tells Demophon that only the sacrifice of a noble woman to Persephone can guarantee an Athenian victory. Macaria volunteers for the sacrifice and a spring is named the Macarian spring in her honor.