Zeus (Greek) / Jupiter (Roman) – a major antagonist in the play, Zeus is introduced in the exposition as "god of flies and death", although he is traditionally associated with sky, lightning, thunder, law, order, and justice.
Orestes (Philebus) – the play's major protagonist, he is the brother of Electra and the son of Agamemnon.
Electra – the sister of Orestes and the daughter of Agamemnon.
Agamemnon – the former king of Argos and the father of Orestes and Electra, Agamemnon was murdered by Aegisthus prior to the story's onset. Orestes' desire to avenge his father's death is a major plot device in the play.
Clytemnestra – the wife of Aegisthus and the mother of Orestes and Electra.
Aegisthus – the husband of Clytemnestra.
Furies – also known as the Erinyes or "infernal goddesses", the Furies serve as Zeus' enforcers in Argos and punish those who swear false oaths.