Orestes returns to Argos several years after the murder of Agamemnon, accompanied by his friend, Pylades. He leaves a lock of hair at his father’s grave. From a distance, they spy Orestes’ sister Electra, accompanied by the chorus of enslaved women. Clytaemnestra has sent them to bring libations for the dead to quiet their spirits. Unsure of what sort of prayer to offer to her father’s spirit, Electra lets the leader of the chorus guide her; they have a mutual hatred of Clytaemnestra. She prays for the safety of her friends, for Orestes to come home, and for the vengeance to come to Aegisthus and Clytaemnestra.

Orestes and Electra are reunited after Electra finds his lock of hair and follows his footprints which are nearly identical to hers. Electra is skeptical at first, then overjoyed. Orestes prays to Zeus to watch over them. The leader of the chorus urges them to be cautious, lest they be overheard. Orestes reveals that Apollo himself charged him with avenging Agamemnon. Failure to do so will invoke the Furies.