Oedipus the King is the best-known play we have from the pen of Sophocles and was recognized as a masterpiece in Aristotle's Poetics, which cites the play more often than any other as an example of how to write tragedy. The principal character is the king of a city ravaged by a mysterious plague, who consults Apollo at Delphi and is told that the plague will end only when those who killed the previous king, Laius, are found and punished. He launches an investigation, in t...