When Agamemnon, the king of Argos, returns home from the Trojan War, he is murdered in cold blood by his wife, Clytemnestra, and her lover, Aegisthus. Afterward, Aegisthus and Clytemnestra are married, and Aegisthus becomes king. Orestes, the young son of Agamemnon, is sent by a relative to Phocis before Aegisthus can destroy him. Electra, the daughter, remains, but is given in marriage to an old peasant, lest she marry a warrior powerful enough to avenge her father’s death.

One day, after Electra and the peasant go out to do the day’s work, Orestes comes in disguise with his best friend, Pylades, to the farm to seek Electra. They hear her singing a lament for her fate and for the death of her father. A messenger interrupts her lament with word that a festival is to be held in honor of the goddess Hera and that all Argive maidens are to attend. Electra says she prefers to remain on the farm away from the pitying eyes of the people of Argos. The messenger advises her to honor the gods and to ask their help. Electra mistakes Orestes and Pylades for friends of her brother. She tells them her story and speaks of her wish that Orestes will avenge the death of Agamemnon and the ill treatment of his children. Aegisthus, meanwhile, offers a reward for the death of Orestes.

The peasant returns from his work and asks Orestes and Pylades to remain as his guests. Electra sends her husband to bring the relative who took Orestes away from Argos. On his way to the peasant’s cottage, the old foster father notices that a sacrifice was made at the tomb of Agamemnon and that there are red hairs on the grave. He suggests to Electra that Orestes might be in the vicinity, but Electra answers that there is no chance of his being in Argos. When Orestes comes out of the cottage, the old man...