In Euripides’s Electra he draws swords with Aeschylus’s much earlier and superior version of the same Orestes story, in The Libation Bearers.
In Aeschylus, there is a kind of hero-worship in which Orestes triumphantly returns to Mycenae and he kills his parents, only to be troubled by the Furies. In Euripides’s version, the story is told from the psychological perspective of Electra, hence the title of the play. She is married to an old peasant to conceal her from the ire of new and unjust rulers of Mycenae. Orestes returns in disguise, somewhat less impressively than in Aeschylus’s play. He remains disguised for half the play until he is finally revealed.
Eventually, Electra’s husband returns with an old servant of the family who recognizes Orestes by a scar on his head, mirroring the recognition of Odysseus in Homer’s Odyssey which is notably different from the Aeschylean tradition. In Aeschylus, Orestes is recognized by a lock of hair at the grave of Agamemnon, which in Euripides is mocked by Electra. In fact, Electra laughs out loud at the thought. At any rate, once they recognize each other, Orestes and Electra devise a plan for him to kill Aegisthus while she kills Clytemnestra. After they kill them both, Electra and Orestes are horrified and wracked with guilt. At the end Clytemnestra’s dead and deified brothers appear and reassure both siblings – the killing was a justified matricide. However, Electra must marry Pylades, Orestes’s companion, and Orestes must be haunted by the Furies until he faces trial in Athens.
The play is about just punishments, redemption, and guilt. As is typical in Euripides, he parts ways with tradition and presents a less common viewpoint, one filled with sorrow and resentiment.