Outside the door to Medea's house in the city-state of Corinth, the Nurse laments that Jason's ship, the Argo, ever sailed to Clochis, Medea's non-Grecian homeland, in search for the Golden Fleece. If the Argo had not sailed for Clochis, the Nurse says, then Medea would never have fallen in love with Jason and sailed with him to his homeland in Greece, Iolcus. And, in Iolcus, Medea never would have tricked king Pelias' daughters into killing Pelias.
Euripides' ancient audience was familiar with the story of Medea. Having the Nurse recount Medea and Jason's past exploits and exiles in her complaints was a deft way for Euripides to situate his audience in the particular moment in the story at which the play begins, in medias res (in the middle of things).
If the Argo had not sailed and Medea had not tricked Pelias' daughters, then, the Nurse says, Medea would never have come to live in Corinth with Jason. Where, the Nurse claims, Medea is hated and Jason has betrayed her and his children by marrying the Princess, the daughter of Creon, the king of Corinth. Medea, meanwhile, according to the Nurse, has been possessed by powerful grief and blinding rage that prohibits her from listening to the wise words of her friends.
The Nurse, as if by accident, lets the audience know the current location (Corinth) and provides us with vital information about the ongoing action—Medea's growing rage over Jason's abuses and over his decision to neglect his familial duties. Euripides characterizes Medea as extremely bold and stubborn, hard-headed and difficult to reason with.
The Nurse describes how Medea weeps for her homeland and everything she left behind to come with Jason who has abandoned her. Furthermore, the Nurse says that Medea now seems to hate her two sons, and that she is dangerous. The Nurse fears Medea is dreaming up a dreadful plan. Just as she says this, the children return home with their Tutor. The Tutor asks the Nurse why she is standing alone by the door talking to herself. She explains that she is so distressed she had to tell Medea's woes to the earth and sky.
We are now fully informed of Medea and Jason's status as exiles and begin to get a sense of the emotional turmoil this status has wrought on Medea. We see how Jason has escaped the anxieties of exile by abandoning his family and marrying into the royal family of Corinth. Euripides begins foreshadowing the innovation he has added to the story of Medea—Medea's brash decision to kill her children. In the traditional mythology of th story, the children were killed in retaliation by the Corinthians after Medea killed Creon and the Princess. Here, also, Euripedes acknowledges the unnatural construction of the Nurse's long, expository monologue via the Tutor's questioning of the Nurse.
As the Nurse and the Tutor discuss Medea's grief, the Tutor lets it slip that he overheard something at the castle concerning Medea. He then tries to pretend he didn't just mention having overheard something. The Nurse, however, convinces the Tutor to tell her what he heard. While walking past the area where old men play dice, he says, he heard them say that Creon is going to exile Medea and her children. The Tutor says he doesn't know if the report is true.
Euripides creates suspense by having the Tutor withhold briefly secret information concerning a rumor of a third exile for Medea. The Tutor waivers between his duty as a servant to avoid spreading gossip and his feeling that he should honor his fellowship to another servant by sharing whatever information he might have.
The Tutor advises the Nurse to keep quiet and hide the rumor from Medea, and the Nurse advises the Tutor to keep the children out of Medea's sight. Just then, Medea cries from inside the house (offstage) that she is wretched and wants to die. The Nurse tells the children to run inside as fast as they can; Medea's wailing is the first danger sign. The boys go inside (offstage). The Nurse is convinced Medea will fan the smoke of her grief into the flame of fury.
The Nurse and Tutor exchange sage advice based on their knowledge of Medea's character and the Nurse's intuition that Medea will commit unnatural crimes against her children. Medea wails because of the pain of exile and the crimes Jason has committed, breaking his oaths and abandoning his family.