Troy, then, had sinned, and has fallen; but (says the Chorus)
let the conquerors look to it that they do not overstep the mark;
let there be no dishonoring the native Gods of Troy; (the
Athenians had been very considerably overstepping the mark
in some of their own conquests recently;)--let there be no
plundering or useless cruelty; (the Athenians had been hideously
greedy and cruel;)--or Karma would overtake it own agents, the
Greeks, who were not yet out of the wood, as we say--who had not
yet returned home. This was when the beacons had announced the
fall of Troy, and before the entry of Agamemnon.

Clytemnestra is not like Gertrude, but a much grander and more
tragical figure. Shakespeare leaves you in no doubt as to his
queen's relation to Claudius; he enlarges on their guilty
passion _ad lib._ Aeschylus never mentions love at all in
any of his extant plays; only barely hints at it here. It
may be supposed to exist; it is an accessory motive; it
lends irony to Clytemnestra's welcome to Agamemnon--in which
only the audience and the Chorus are aware that the lady
does protest too much. But she stands forth in her own eyes
as an agent of Karma-Nemesis; there is something very terrible
and unhuman about her. Early in the play she reminds the
Chorus how Agamemnon, is setting out for Troy, sacrificed
his and her daughter Iphigenia to get a fair wind: a deed
of blood whose consequences must be feared--something to
add to the Chorus's misgivings, as they chant their doubtful
hope that the king may safely return. In reality Artemis
had saved Igphigenia; and though Clytemnestra did not know
this, in assuming the position of her daughter's avenger