Apollo gives an order through the Oracle at Delphi that Agamemnon's son, Orestes, is to kill Clytemnestra and Aegisthus, her lover.

On Agamemnon's return from Troy he was murdered ( according to the fullest version of the oldest surviving account, Odyssey 11. 409 – 11 ) by Aegisthus, the lover of his wife Clytemnestra.

Clytemnestra, Agamemnon's wife, had taken Aegisthus, son of Thyestes, as a lover.

When Agamemnon came home he was slain by either Aegisthus ( in the oldest versions of the story ) or Clytemnestra.

Agamemnon's son Orestes later avenged his father's murder, with the help or encouragement of his sister Electra, by murdering Aegisthus and Clytemnestra ( his own mother ), thereby inciting the wrath of the Erinyes ( English: the Furies ), winged goddesses who tracked down egregiously impious wrongdoers with their hounds ' noses and drove them to insanity.

Aegisthus and Thyestes thereafter ruled over Mycenae jointly, exiling Atreus ' sons, Agamemnon and Menelaus to Sparta, where King Tyndareus gave the pair his daughters, Clytemnestra and Helen, to take as wives.

While Agamemnon, the son of Atreus, was absent on his expedition against Troy, Aegisthus seduced Clytemnestra, the wife of Agamemnon, and was so wicked as to offer up thanks to the gods for the success with which his criminal exertions were crowned.

Unbeknownst to Agamemnon, while he was away at war, his wife, Clytemnestra, had begun an affair with Aegisthus.

In Aeschylus's Oresteia, the story is begun with Agamemnon's return home, to find that his wife, Clytemnestra, had married her lover, Aegisthus.

Incidentally, Telemachus learns the fate of Menelaus ’ brother Agamemnon, king of Mycenae and leader of the Greeks at Troy: he was murdered on his return home by his wife Clytemnestra and her lover Aegisthus.

Many of the Greek wives were persuaded to betray their husbands, most significantly Agamemnon's wife, Clytemnestra, who was seduced by Aegisthus, son of Thyestes.

His wife Clytemnestra ( Helen's sister ) was having an affair with Aegisthus, son of Thyestes, Agamemnon's cousin who had conquered Argos before Agamemnon himself retook it.

He killed Clytemnestra and Aegisthus and succeeded to his father's throne.

In Euripides ’ other story about Iphigenia, Iphigenia in Tauris, the play takes place after the sacrifice and after Orestes has killed Clytemnestra and Aegisthus.

She and her brother Orestes plotted revenge against their mother Clytemnestra and stepfather Aegisthus for the murder of their father, Agamemnon.

Electra was absent from Mycenae when her father, King Agamemnon, returned from the Trojan War to be murdered, either by Clytemnestra's lover Aegisthus, by Clytemnestra herself, or by both.

Aegisthus and Clytemnestra also killed Cassandra, Agamemnon's war prize, a prophet-priestess of Troy.

Pylades and Orestes killed Clytemnestra and Aegisthus ( in some accounts with Electra helping ).

On the other hand, Sophocles does mention her, and hints that she lives in the palace of Aegisthus and Clytemnestra, together with Electra and Chrysothemis.

With his friend Pylades ' assistance, Orestes murders mother Clytemnestra and her lover Aegisthus.

While he was fighting the Trojans, his wife Clytemnestra, infuriated by the murder of her daughter, began an affair with Aegisthus.

When Agamemnon left Mycenae for the Trojan War, Aegisthus seduced his wife, Clytemnestra, and the couple plotted to kill her husband upon his return.

Clytemnestra and Aegisthus had three children: Aletes, Erigone, and Helen, who died as an infant.

Unlike her sister, Electra, Chrysothemis did not protest or enact vengeance against their mother for having an affair with Aegisthus and then killing their father.

Aegisthus then killed Atreus, although not before Atreus had two sons, Agamemnon and Menelaus.

Aegisthus then killed Atreus.

Aegisthus then killed Atreus and restored the kingdom to Thyestes.

This was one of the sources of the curse that destroyed his family: two of his sons, Atreus and Thyestes, killed a third, Chrysippus, who was his favorite son and was meant to inherit the kingdom ; Atreus and Thyestes were banished by him together with Hippodamia, their mother, who then hanged herself ; each successive generation of descendants suffered greatly by atrocious crimes and compounded the curse by committing more crimes, as the curse weighed upon Pelops ' children, grandchildren, and great-grandchildren including Atreus, Thyestes, Agamemnon, Aegisthus, Menelaus, and finally Orestes, who was acquitted by a court of law convened by the gods Athena and Apollo.

Orestes kills Aegisthus and then he alone goes to Clytemnestra's bed chamber and kills her as well.

Aegisthus took possession of the throne of Mycenae and ruled jointly with Thyestes.

Homer appears to know nothing of all these tragic occurrences, and we learn from him only that, after the death of Thyestes, Aegisthus ruled as king at Mycenae and took no part in the Trojan expedition.

In old versions of the story: " The scene of the murder, when it is specified, is usually the house of Aegisthus, who has not taken up residence in Agamemnon's palace, and it involves an ambush and the deaths of Agamemnon's followers too ".

Seven or eight years after the death of Agamemnon, Agamemnon's son Orestes returned to Mycenae and, with the help of his cousin Pylades and his sister Electra, killed both their mother, Clytemnestra, and Aegisthus.

When King Agamemnon returns from the Trojan War with his new concubine, Cassandra, his wife Clytemnestra ( who has taken Agamemnon's cousin Aegisthus as a lover ) kills them.

Orestes explains that he has avenged Agamemnon's death by killing Clytaemnestra and Aegisthus.

Agamemnon arrives home and is there murdered by his wife Clytemnestra and her lover, Agamemnon's cousin Aegisthus.

Menelaus succeeded Tyndareus in Sparta, while Agamemnon, with his brother's assistance, drove out Aegisthus and Thyestes to recover his father's kingdom.

After his return to Greece, Orestes took possession of his father's kingdom of Mycenae ( killing Aegisthus ' son, Alete ) to which were added Argos and Laconia.

Aegisthus called for Pelopia, who told him how the weapon had got to her.

She saved his life by sending him to Strophius after the murder of Agamemnon, whereas Aegisthus killed her own son, taking him for Orestes.

In The Eumenides of Aeschylus ( 458 BC ), the Areopagus is the site of the trial of Orestes for killing his mother ( Clytemnestra ) and her lover ( Aegisthus ).

Set in the city of Argos a few years after the Trojan war, it is based around the character of Electra, and the vengeance that she and her brother Orestes take on their mother Clytemnestra and step father Aegisthus for the murder of their father, Agamemnon.

Despite her appreciation for her peasant husband, Electra resents being cast out of her house and her mother's loyalty to Aegisthus.

Orestes goes to the ceremony of the dead, where the angry souls are released by Aegisthus for one day where they are allowed out to roam the town and torment those who have wronged them.

In repudiating the murders of Clytemnestra and Aegisthus, Electra allows Zeus to determine her past for her.

Unlike in Aeschylus ’ The Libation Bearers, where revenge is one of the main themes throughout the play, Sartre ’ s Orestes does not kill Aegisthus and Clytemnestra for vengeance or because it was his destiny, instead it is for the sake of the people of Argos, so that they may be freed from their enslavement.