Aeschylus' The Libation Bearers is the second in the Oresteia. It mainly deals with the reunion of Agamemnon's children, Electra and Orestes.
Electra arrives at the grave of her father to pour a libation, and comes upon a man in the graveyard, whom she believes must be her estranged brother. Together, they plan to avenge their father by killing Clytemnestra and her new husband, Aegisthus.
Orestes is not sure that he ought to kill Clytemnestra, since she is his mother, but is guided by Apollo and his friend (I forget the name) that it is the correct course of action.
The play ends with the death of Clytemnestra and the knowledge that the Furies will begin to haunt and torture Orestes for his crime.
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