The scene begins at the mountain cavern, which is blocked at the entrance by a large black boulder; there is a crowd present for the ceremony. A woman teaches her child to cry on cue, to be frightened by the spirits who are about to exit from the cavern. This shows the extent to which Aegistheus has manipulated people into subservience through fear, and this is what Sartre attacks vehemently: No outside authority should ever be permitted to control our thoughts, feelings, and choices in life — and this includes political, religious, social, and other types of authority figures. Aegistheus symbolizes the state, whereas Zeus represents God and the Church: Sartre rejects them both as evils to humanity. This is an ideological play; Sartre is not concerned with developing a psychological drama (although indeed elements of psychology are part of it). He is interested in ideas, not in aesthetic beauty, and he paints the picture of gloom and doom with broad strokes of black and colorless adjectives.
Zeus enters with Orestes and the Tutor, who reacts to the ugliness of the Argos citizens. The Tutor is glad that he, unlike the citizens, still has rosy cheeks, but Zeus startles him by saying, "You're no more than a sack of dung, like all those others. These folk, at least, know how bad they smell." Sartre uses Zeus shrewdly; he is a device whose function it is to express ideas contrary to those of Sartre (and Orestes). Zeus symbolizes the enemies of freedom (the government, the Church — anything totalitarian), and he represents all those who use tricks to remove freedom from the lives of others. Since he espouses ideas opposite to Sartre's, he is used by Sartre to give Orestes the possibility to express existential ideas. Zeus, thus, becomes part of Sartre's dramatic technique: He, like other enemies of freedom, wishes for men to have remorse since the fear of remorse prevents men from acting, from choosing; this fear eliminates freedom, and if we have remorse, claims Sartre, it is because we have not acted.
Aegistheus arrives with Clytemnestra and the High Priest. Electra is not present, and Aegistheus is angry. The boulder is rolled away from the cave's entrance, and the High Priest addresses the dead spirits: "Arise, this is your day of days." All the trappings of a primitive religious ceremony are present: tom-toms, dances, gyrations, and so on. Orestes says that he cannot bear to watch them, but Zeus tells him to look in his, Zeus', eyes; this silences Orestes. The crowd cries out for mercy, but Aegistheus tells them that they will never have it, that one cannot atone for sins when the person against whom a sin was committed has died. It is an ugly, hopeless atmosphere. Aegistheus announces that the ghost of Agamemnon is coming forth, and Orestes, offended by this nonsense, draws his sword and forbids him to make Agamemnon a part of this "mummery." Zeus intervenes, telling Orestes to stop, and Electra enters, dressed in white. She is quite a contrast to the black of the mob, and everyone notices her. The crowd wants to be rid of her, especially after Aegistheus reminds everyone of her treacherous blood ("the breed of Atreus, who treacherously cut his nephews' throats"). She retorts that she is happy for the first time in her life, that Agamemnon lovingly visits her by night with his secrets, and that he smiles on her present actions. The crowd isn't so sure and thinks that she has gone mad. She explains to them that there are cities in Greece where people are happy, where children play in the streets. This is a direct influence from Orestes. She tells the crowd that there's no reason to be afraid: She is the first glimpse of freedom that they've had in fifteen years, and it is only through contact with Orestes that she has been able to experience this radiance. The crowd sees that she is truly happy, and they comment on her ecstasy. They confront Aegistheus openly: "Answer us, King Aegistheus. Threats are no answer." Someone calls Aegistheus a liar. But Zeus, seeing the surge of interest in freedom, puts an end to it: He causes the boulder to come crashing against the temple steps, and this is enough to instill fear in the crowd again. Electra stops dancing. The flies swarm everywhere. Aegistheus sends everyone home and banishes Electra from the city. Orestes, furious about the turn of events, orders Zeus to leave him alone with his sister. This shows that Orestes is not afraid of Zeus and is willing to take action on his own, despite the god's interference. Orestes has been exposed to the cruelty and punishment of the townsfolk, and soon he will be committed to a new lifestyle: He will give up his detachment and will engage himself in a fight to save them.
Orestes tells Electra that she cannot stay in the city a moment longer; the two of them must flee. But she refuses and blames him for her lack of success with the crowd; she is not angry with him, but he made her forget her hatred, which was her defense against Aegistheus's tyranny. She does not want a peaceful flight with him: "Only violence can save them." She claims that her brother will come to her assistance. Orestes then identifies himself as her brother and confesses that he was reared by some wealthy Athenians, and not in Corinth, as he stated earlier. Zeus arrives to eavesdrop on them. Electra has mixed emotions about Orestes; she says that she loves him, but then she declares her fantasy-version of Orestes as being dead; the real Orestes, she claims, has not shared in her bloody, unhappy past and cannot be part of the vengeful present: "Go away, my noble-souled brother. I have no use for noble souls; what I need is an accomplice." She announces her desire: to have someone who will assist her in the murder of Clytemnestra and Aegistheus. Orestes describes how his life to date has been uncommitted to anything and that he has nowhere to go if Electra sends him away. He wants to engage himself (in an existential act): "I want my share of memories, my native soil, my place among the men of Argos." This is a difficult moment for Orestes since he has to convince Electra of his reason for staying in Argos. It is the one point along his journey to commitment where he feels an uncertainty about what to do. He hesitates for a moment, then asks Zeus what to do. "O Zeus . . . I can no longer distinguish right from wrong. I need a guide to point my way." He does not know that Zeus, the enemy of freedom, is lurking in the wings; he addresses the legendary Zeus who is god of all gods. He tells Zeus that if the god wants him to remain passive and accepting of reality, he need only send a sign. The living Zeus is delighted and sends flashing bolts of light; this sign of light indicates to Orestes that he should give in, leave Argos, and not become committed. Electra laughs at Orestes for having consulted a god. Orestes quickly realizes that it is dangerous to entrust one's decisions to the feelings of other people. He recovers from his moment of weakness and decides to commit himself firmly: "It's not for me, that light; from now on, I'll take no one's orders, neither man's nor god's." Electra notices that a change has come over his face and voice. Clearly, Orestes knows that he must take on the burden of responsibility. This is the turning point of the play: Orestes says good-bye to his youth and his uncommitted days, and he launches forth into a path of action which will undo the tyrannical regime. As a Christ-like figure, he intends to take over the crimes of the suffering people of Argos. Electra shows signs already of being weak; she is not sure that she can go along with Orestes. He asks her to conceal him in the palace and, at night, to lead him to the royal bedchamber.