1. Agamemnon: Agamemnon comes home from the Trojan war, after being away for ten years. His wife, Clytaemnestra, has been resentful of the fact that he sacrificed one of their daughters, Iphigeneia, at the outset of his journey, apparently because Artemis would not provide the necessary winds without a sacrifice. Also, she -- Clytaemnestra -- has been getting it on with Agamemnon's cousin, Aegisthus, for some time. So when Agamemnon gets home, she coerces him into walking on some fancy tapestries, or something, because I guess this qualifies as hubris and will put him out of favor with the gods? Then she kills him while he's in the tub (not classy). Then she kills Cassandra, whom he'd brought back with him as a slave.
2. The Libation Bearers: Some uncertain number of years later, Orestes, -- the son of Agamemnon and Clytaemnestra -- who has long been elsewhere, returns to Argos and reunites with his sister, Electra, whom he finds mourning at their father's grave. They agree that their father was awesome and their mother sucks, and they hatch a plan to kill her. Orestes heads to the palace in disguise and proceeds to kill Aegisthus and Clytaemnestra.
3. The Eumenides: The Furies, who traditionally punish those who kill their mothers,* are after Orestes. Apollo tells them to cut it out, because the murder was justified and he told Orestes it was ok. The Furies are pissed about this, and Athena comes in to mediate. She ends up holding a little trial for Orestes; the jury is tied, so Athena breaks the tie in Orestes' favor. The Furies are pretty much shitting bricks until Athena, in essence, convinces them to use their power for good rather than evil. And they all lived happily ever after, the end.
Ok. So that's all very well and good, and you probably didn't need all that background, but there it is just in case. HERE IS THE PART THAT IS BREAKING MY BRAIN.
During the whole Apollo-Orestes-Furies disagreement, Orestes summons Athena to come help out. And in she comes:
Enter ATHENA, armed for combat with her aegis and her spear.
ATHENAReally, Athena? You just came from the Trojan war, just now? Because I am pretty sure it ended YEARS ago. Like, before Agamemnon came home. I mean, I don't think he bailed before the job was done, or anything. Are you a very, very slow traveler? Is there a hole in the space-time continuum?
From another world I heard a call for help.
I was on the Scamander's banks, just claiming Troy.
The Achean warlords chose the hero's share
of what their spear had won -- they decreed that land,
root and branch all mine, for all time to be,
for Theseus' sons a rare, matchless gift.
Home from the wars I come, my pace unflagging,
wingless, flown on the whirring, breasting cape
that yokes my racing spirit in her prime. (The Eumenides 408-16)
Athena, I never ask you where you really were when you come home at four am and claim you were "just out with friends." I respect your privacy, Athena. So why would you lie to me? It hurts me when you lie.
*I love the exchange during which they explain this duty to Apollo:
Authority -- you? Sound out your splendid power.
Matricides: we drive them from their houses. (The Eumenides 207-8)
How's that for a company slogan? Matricides: we drive them from their houses!