Electra discovers a lock of hair on Agamemnon's grave. The chorus becomes agitated, asking whose it is. Electra says that it is identical to her own. She knows that it is Orestes's hair, for she can see his curls, and assumes that he sent it in order to honor their father. The chorus says that it is all the more cause for grief, as it must be a sign that Orestes will never return.
Electra gives a long, emotional speech, torn by the hope that the lock of hair might actually belong to her brother. She wishes the lock of hair could speak and tell her where it came from. She then finds a second sign, a set of footprints that match her own in proportions. Her mind is reeling with shock and anticipation.
Suddenly, Orestes enters and tells Electra to thank heaven for fulfilling her prayers. She asks how so, what prayer has been answered? He says that she sees her wish come true, and that he is Orestes. She disbelieves him, saying it must be a trick, or that he is mocking her. He says that he shares her distress, and if he were to mock her, he would be mocking himself. When she continues to doubt, Orestes calls her a slow learner. He challenges her to hold up the lock of hair to his head and see how it matches, and also provides the third token of a piece of weaving he has that she made herself.
Electra finally gives in to her hope and rejoices. She implores him to save their father's house. She says that four aspects of her love now belong to Orestes: that which should go to Agamemnon, who is dead, that which should go to Clytamnestra, who murdered Agamemnon, that which should go to Iphigineia, who was killed by Agamemnon, and that which naturally would go to Orestes as her brother. She hopes that Might, Justice, and Zeus himself will help him in his quest.
This section of the text covers the recognition scene between Orestes and Electra. There are three stages. First, Electra discovers the lock of hair. Instead of telling her how to speak, the chorus is suddenly asking her for information. In this special case, the young will teach the old rather than the other way around. Electra says that someone could have brought it from her brother as a message. Second, Electra discovers the footprints. She begins to realize that Orestes himself must have left the hair on the grave. Third comes the confrontation between brother and sister, with the final proof of embroidery from Orestes.
Electra's hope that the lock of hair might have come from Orestes seems almost comically coincidental, until we realize that only a family member would have been likely to leave a lock of hair on Agamemnon's tomb. Since she knows that she did not leave it, and that her mother never would have, her assumption that it belongs to her brother is not as ridiculous as it first appears.
Having followed the clues to Orestes himself, Electra then refuses to recognize him at first. In her inability to follow her own logic, she shows herself to be the opposite of her mother, who is relentless in her ability to manipulate logic and language towards her own ends. Emotional wavering and irrational hoping are strong feminine traits. Clytamnestra, on the other hand, is portrayed in the Agamemnon as possessing strong male tendencies, which a Greek audience would have found disturbing. Unlike her mother, Electra plays an appropriate female role. Electra has said that she wishes to be entirely different from her mother (line 140–141), and here we see her fulfilling that desire.
Orestes's first words to his sister are that she should thank the gods for fulfilling her prayers. Just as Electra appeared immediately after Orestes prayed for help in avenging his father's death, so Orestes appeared after Electra wished for the same. Electra should be grateful, as the gods are clearly on their side. The immediate fulfillment of some part of their prayers indicates that their main wish will also come true, that Clytamnestra and Aigisthos will pay for their crimes.
Electra doubting of Orestes's words is significant in the context of the trilogy, as Clytamnestra lured Agamemnon to his death with persuasive words. She says, "No, it's a trap, stranger a net you tie around me?" This strongly evokes the high-pitched scene in the Agamemnon when Cassandra recognizes Clytamnestra for the murderer that she is: "No no, look there!— what's that? some net flung out of hell—No, she is the snare." Orestes assures his sister that he is on her side. Her pain is his own. They are to work together to devise plots against the queen herself. The lock of hair and the footprints were signs of a deep affinity, the strongest of blood ties.