Oedipus play was "Laius", the second was "Oedipus", and the third was "Seven against Thebes". Only the third play survives, in which Oedipus' sons Eteocles and Polynices kill each other warring over the throne. Much like his "Oresteia", this trilogy would have detailed the tribulations of a House over three successive generations. The satyr play that followed the trilogy was called "The Sphinx". As Sophocles' "Oedipus Rex" begins, the people of Thebes are begging the king for help, begging him to discover the cause of the plague. Oedipus stands before them and swears to find the root of their suffering and
Oedipus at Colonus of guilt; the fact that Oedipus is "rationally innocent" – that he sinned unknowingly – decreases his guilt, allowing his earthly sufferings to serve as sufficient expiation for his sins. Darice Birge has argued that "Oedipus at Colonus" can be interpreted as a heroic narrative of Oedipus rather than a tragic one. It can be viewed as a transitional piece from the Oedipus of "Oedipus Rex" whose acts were abominable to the Oedipus we see at the end of "Oedipus at Colonus", who is so powerful that he is sought after by two separate major cities. The major image used