Orestes and Electra were children of Agamemnon and Clytemnestra. Their sister Iphigenia had been sacrificed by Agamemnon at the beginning of the Troian war. When he 10 years later returned, he was murdered by Aegistus, Clytemnestra's lover. When Orestes and Electra, who both had been brought to safety, return and meet they plan and execute the murder of both lovers