King Creon of Corinth wants to secure his throne. In order to do this, he wants to marry the successful warrior Jason to his daughter Glauce. Jason accepts, but he is already married to Medea. Since Medea is known as a wise woman, Creon feels need to banish Medea and her two boys from the city. She begs him to let him stay, but he gives her only one day in order to secure the needs of the two boys.
Medea makes an agreement with the king of Athens, Aegeus, that she and the two boys can come live in Athens with his protection. She then plans to murder both Glauce and Creon and eventually her own children.