At the outset of the play, Oedipus is the beloved ruler of the city of Thebes, whose citizens have been stricken by a plague. Consulting the Delphic oracle, Oedipus is told that the plague will cease only when the murderer of Queen Jocasta's first husband, King Laius, has been found and punished for his deed. Oedipus resolves to find Laius's killer. His investigation turns into an obsessive reconstruction of his own hidden past when he discovers that the old man he killed when he first approached Thebes as a youth was none other than Laius. At the end, Jocasta hangs herself in shame, and the guilt-stricken Oedipus blinds himself.