The Oresteia - by Aeschylus

I've just finished re-reading Aeschylus' tragedy "The Oresteia", the story of the cursed royal family of Mycenae: blood that cries for more blood.

William Adolphe Bouguereau - The remorse of Orestes (1862)
Orestes is tormented and haunted by the Furies after having murdered Clytemnestra

The Cast

Agamemnon: king of Mycenae, leader of the Greek armada against Troy.
Clytemnestra: wife of Agamemnon.
Orestes, Iphigenia, Electra: children of Agamemnon and Clytemnestra.
Aeghistus: Clytemnestra's lover, cousin of Agamemnon.
Cassandra: daughter of Priam (king of Troy), Agamemnon's lover and captive.
The Furies: the three female deities of vengeance, persecutors of mortals who killed members of their own family.

Note: I would suggest you start reading "The anger of Achilles"

The story

Divided into three "acts" (Agamemnon, The Libation Bearers, The Eumenides) the trilogy goes around the numerous family-bloody-homicides in the house of Atreus: "life for life, eye for eye, tooth for tooth, hand for hand" seem to be the essence of each murderous act. Along the play we come across filicide (the killing of one's children), mariticide (the killing of one's husband) and matricide (the killing of one's mother) in a chronological order subject to a pay-back desire. Mother and siblings join their partners side by side and enjoy the butchering of each other.

- Agamemnon kills his daughter Iphigenia
At the start of the Trojan expedition Agamemnon has to take the unwanted decision of sacrificing his daughter Iphigenia in order to appease the goddess Artemis and gain favourable winds to sail to Troy. Clytemnestra, his wife, will never forgive him.

"Tragedy is not a struggle between good and evil, but a contest between two mutually exclusive goods" (David R. Slavitt)

- Clytemnestra avenges her daughter by killing Agamemnon
The victorious leader of the Achaean army returns from Troy with her captive Cassandra. As soon as they steps inside his house, his wife and her lover (Aeghistus) stab them to death in a bloody bath rejoiced by bothe killers.

Clytemnestra: "I killed him, struck him down (...) I'm proud. I threw his robe around him (...) and he couldn't see, or fight or escape, and I stabbed him. Twice ! (...) He bled like a pig! It spurted out and splashed me, and I was delighted. A farmer, wet in the rain of the spring that will give him his crops, could not be more happy and grateful than I was then! I bloomed like a whole garden of flowers in that downpour of Agamemnon's blood. (...) "

Aeschylus (The Oresteia) / Euripides (Oedipus Rex): "Call no man's life happy until it has come to its end".

Agamemnon thought he had everything (honor, esteem, respect, power ... ) in order to find out he was sentenced to die in the hands of his own wife.

- Orestes and Electra kill their mother Clytemnestra
Back from exile, Orestes joins his sister Electra and plot the murder of Aeghistus and Clytemnestra to avenge the killing of their father Agamemnon.

Apart from the numerous homicides of the royal family, the Furies gain a significant role in the play as the persecutors of our main character Orestes. The son of Agamemnon has to run away and seek for the help of Apollo,  god and principal promoter of Orestes' matricide. To escape the avenging deities the mortal agrees to put his fate in the hands of Athena, who acts as judge of the first-ever court trial held. Orestes is acquitted of murder and after a long and hard negotiating period with the Erinyes (another name for "The Fates"), the latter  join Athena in the process of glorifying the city of Athens.

Seen form a different angle and taking to account that Aeschylus wrote the play in Pericles' time, the story unveils the beginning of the democratic system in Athens.