It is often said that there can't be any higher tragedy than the one found in the life of Oedipus Rex. Oedipus Rex was first performed c. 429 BC in an ancient Greek theatre. Sophocles had written three Theban plays in a series and Oedipus Rex was the second of the plays to be produced. In the internal chronology, Oedipus Rex comes first. The other two plays in the chronology were "Oedipus at Colonus" and "Antigone". Oedipus Rex has been the source of inspiration for many great playwrights over the centuries and even today it is regarded as the Greek Tragedy which is unmatched, for it takes Tragedy to the point whence there is no further climb. It is the extremity of pain and agony.