Clytemnestra.

About Clytemnestra

In Greek mythology, Clytemnestra is the wife of Agamemnon, king of Mycenae, and the half-sister of Helen of Troy. With Agamemnon, she is the mother of Iphigenia, Orestes, Electra, and Chrysothemis. She appears as a character in multiple ancient Greek works, including the Homeric epics and plays by Aeschylus, Sophocles, and Euripides. She is infamous for murdering Agamemnon and the Trojan princess Cassandra, whom Agamemnon had taken as a war prize, when they returned from the Trojan War. In Homer's Iliad, her role in Agamemnon's death is unclear and her character is significantly more subdued. However, in the Odyssey, Agamemnon's ghost tells Odysseus about Clytemnestra's role in his brutal murder.