The play begins with a Watchman, who is stationed on the roof of the palace of Atreus in the Greek city of Argos. The Watchman prays to the gods that his job will soon be done, as he has been stationed there for a full year. The queen of Argos, Clytemnestra, has instructed him to watch for a signal fire from Troy. The signal fire would indicate that her husband Agamemnon’s army has taken the city and is victorious in the Trojan War.
The fact that the play begins with a prayer immediately introduces the idea that many of the characters believe that the gods are determining their fates. Knowledge of the Trojan War is assumed for the play’s audience, as the war is an important part of Greek mythology and the subject of Homer’s famous epic poem the Iliad.
The Watchman feels that Clytemnestra has unsettlingly masculine qualities, and explains that he cannot sleep because of his deep sadness and fear concerning the state and current governing of the House of Atreus.
From the very first time Clytemnestra is mentioned, her femininity is called into question. The Watchman’s observation of Clytemnestra’s “masculine” qualities is directly followed by his admission of his fears about the royal family, subtly linking the two ideas.
All of a sudden, the signal fire blazes from Troy. The Watchman, in a joyous state, cries out that the Trojan War is over, and he jumps up to inform Clytemnestra. Then his mood changes abruptly as he wishes Agamemnon a safe return, and once again he expresses a vague sense of some mysterious and sinister activities that have occurred in the palace, but he refuses to elaborate on what these may be.
An ancient Greek audience would have understood that the Watchman is referring to a curse on the House of Atreus—a series of violent tragedies that have been occurring (and will continue to occur) in Agamemnon’s family for generations. One of the root causes of this curse was Agamemnon’s father Atreus, who cooked the children of his brother Thyestes and fed them to him. This is the ultimate heinous act (and so punishable by a multigenerational curse from the gods), but also the ultimate act of revenge, as Thyestes had slept with Atreus’s wife and temporarily stolen his kingdom. The Trojan War’s end sets the action of the play into motion.
The Watchman exits into the palace to inform the queen that he has seen the signal fire, and the Chorus enters. The Chorus (which speaks all together) is made up of a group of elderly citizens of Argos, men too old to fight in the Trojan War. The members of the Chorus explain that the war is an act of revenge: Agamemnon and his brother Menelaus raised an army from across all the cities of Greece and led it against Troy ten years ago, to get revenge on the Trojan prince Paris for stealing Menelaus’ wife, Helen.
This long speech from the Chorus serves as the main source of exposition for the circumstances of the play. In this explanation, it becomes clear that personal revenge is the primary motivation for the entire Trojan War, again demonstrating revenge’s role as the catalyst for the action of this play (and others). Here the Chorus also introduces the concept of the Furies, the group of divine beings that inspire and enact revenge.
The Chorus then explains that during the war, the goddess Artemis had sent strong winds to delay Agamemnon’s fleet from arriving in Troy. In order to appease Artemis, the army’s prophet suggested that Agamemnon sacrifice his and Clytemnestra’s daughter Iphigenia, and Agamemnon did so. The Chorus then finishes by reminding us that these events of the past, as well as those to come, have all been predetermined. But, as Clytemnestra enters, they express hope that the coming events will be good ones.
Although the reason for Artemis’s anger at Agamemnon is not agreed upon by scholars, what is clear is that Artemis’s decision to delay the fleet is meant to punish Agamemnon for some slight against her—blocking the fleet’s passage is a form of revenge. In addition, Artemis’s involvement in Agamemnon’s wartime decision-making further illustrates the control that the divine world has over the mortal world. Finally, the sacrifice of Iphigenia—necessary for Agamemnon to pursue the Greek war of revenge against the Trojans—begins one cycle of revenge that is central to the play.
The Chorus implores Clytemnestra to tell them what has happened, and she gives them the good news that Agamemnon’s army has taken Troy. Although overjoyed, the Chorus can barely believe the news. They ask Clytemnestra multiple times if the news is true, leaving her feeling belittled.
Clytemnestra describes to the Chorus the system of signal fires that was used in order relay the news to Argos, and then goes on to report what she has heard about the status of Troy. She explains that while the Trojans are in a chaotic and painful state of mourning, Agamemnon’s army is enjoying the spoils of war. She hopes that the Greek army’s looting won’t make them look unfavorable in the eyes of the gods, and prays for their safe return. She goes on to say that even if the army is able to return without offending the gods, they should take extra care, because disaster could strike at any moment. As she exits, the Chorus thanks her for speaking like a wise man, and it prepares to pray.
Clytemnestra’s awareness that the Greeks’ victorious looting could anger the gods shows how even in victory there exist seeds of future destruction – just as even those righteously seeking revenge always seem to end up bring the gods’ anger down on themselves. This also foreshadows how Agamemnon’s own victory will lead to his death. Clytemnestra’s concern for new disaster could be a snide allusion to her own murderous plot. Once Clytemnestra has relayed all of the information in a way that satisfies the Chorus, they praise her for speaking like a man, further reinforcing the differing expectations placed upon men and women in this society.