This has really got to be one of the most messed up of all Greek myths. When a guy kills his brother's kids and tricks him into eating them, even the most cold-hearted people have got to stop and say, "..............he did what?" What's even more horrific is that this isn't the first time killing kids and eating them has popped up in the family of Atreus and Thyestes. In some versions of this tale, their granddad, Tantalus, chopped up their father, Pelops, and tried to feed him to the gods.
Later on, Atreus's son, Agamemnon, is forced by Artemis to sacrifice his daughter, Iphigenia. Though there's no cannibalism involved in Iphigenia's case, the theme is still pretty darn present. Some scholars believe that this theme of child sacrifice reflects the fact that it was once a part of super ancient Greek society. The horror in which these stories are told expresses the Greeks' or the Classical World's horror over the brutality of the past.
Atreus and Thyestes don't put in a personal appearance in the many plays about their famous descendants Agamemnon, Menelaus, Aegisthus, Orestes, Iphigenia, and Electra, the most famous of these probably being Aeschylus's Oresteia trilogy, Sophocles' Electra, and Euripides' Iphigenia at Aulis. All the tragic things that happen to their descendants, though, are sometimes blamed on them. This is especially true of the House of Atreus, whose lives are a regular blood bath, until Orestes finally cleanses the family of its curse. Sometimes this curse is seen as going even farther back than Atreus and Thyestes, however, as some blame Tantalus for first bringing the curse on the house.
One of the more complete versions of the bloody tale of Atreus and Thyestes is told by Hyginius in Fabulae. The only play version we have still around is Thyestes by the Roman playwright Seneca the Younger. There's also a modern version of this play by big-time British playwright, Caryl Churchill. The story of these two bloody brothers might be most famous for inspiring Shakespeare's horrific tragedy, Titus Andronicus, which gives Seneca's Thyestes a run for its money in the realm of brutal revenge.