Clytamnestra pleads once more, saying that she gave him life, and that he should let her grow old with him. Orestes balks, recalling the murder of his father. She claims that destiny was responsible for his death. Orestes counters by saying that destiny also has a hand in her death.
Clytamnestra warns him that he should fear a mother's curse. Orestes cries that she bore him and then abandoned him, selling him off for a price. Clytamnestra challenges him to name the price, and to name his father's failings. Orestes reproaches her, saying that she can never judge a man who was fighting for her while she sat at home.
Clytamnestra shrieks, seeing murder in her son's eyes. She warns him of her curse, and then recognizes him as the snake from her dream. Orestes pronounces that she has killed in an outrageous manner, and now she will suffer the same outrage now. He pulls her over the threshold and they disappear behind the palace door.
This scene is the climax of the play. Aigisthos, secondary to the action throughout the Oresteia, is quickly taken care of so that we may concentrate on the murder of Clytamnestra. It is only at this dreadful moment that Orestes finally faces the awful nature of his duty: matricide. Although the lines fly back and forth and the action proceeds quickly, the scene is still full of pathos and suffering. We see that Orestes has fully accepted his charge, as he counters every pitiful argument from Clytamnestra with a fiercely logical response. The time for discussion and planning is finally over.
Before going into a detailed discussion of Clytamnestra's death scene, we must note one interesting aspect of Aigisthos's speech as he goes unknowingly to his death. He says that no man can deceive him, for his mind is literally "full of eyes." While under normal circumstances this would ensure his protection, as he would see Orestes coming and be able to defend against him, there are more powerful forces at work here. We remember that in the previous scene, the chorus called on Hermes to aid Orestes in his quest. Hermes is the mythological guide, the one who lights the way. But, he is also the trickster, able to make dark and hidden what should be clear before men's eyes. Thus, neither Aigisthos nor Clytamnestra realizes with whom they are dealing until it is too late.
Clytamnestra shows herself far more aware than her unfortunate mate when she immediately interprets the servants cryptic words, "The dead are killing the living," to mean that some agent of Agamemnon has returned to exact vengeance on the house. Realizing that some treachery is afoot, she says, "By cunning we die, precisely as we killed." The servant's line is fascinating in its ambiguity. We can take it to mean either that Agamemnon is killing Aigisthos, or that Orestes is killing him, as Clytamnestra and Aigisthos had thought Orestes to be dead. It is unclear, however, whether Clytamnestra realizes that her son is in fact alive and out for blood until he bursts out of the palace and confronts her face to face.