Warned by an oracle that he is fated to kill his father and marry his mother, the young man raised in Corinth as Oedipus flees the city rather than risk it, not knowing that Polybus and Merope, the king and queen who raised him, are not his birth parents at all. On the road he quarrels with an older man at a narrow crossroads over right of way and kills him along with most of his retinue, not recognizing the man as Laius, king of Thebes and his true father, sent away at birth on a prophecy identical to the one Oedipus is now fleeing.
Continuing toward Thebes, Oedipus meets the Sphinx, a winged lion bodied creature with a woman's face who has been killing every traveler unable to answer her riddle, what walks on four legs in the morning, two at noon and three in the evening. Oedipus answers correctly, man, who crawls as an infant, walks upright in his prime and leans on a staff in old age, and the Sphinx, defeated, destroys herself. Thebes, freed from her terror and left without a king after Laius's unexplained death, gives Oedipus the throne and the hand of the widowed queen Jocasta in marriage, completing the second half of the prophecy exactly as unknowingly as the first.