The play opens at night in Venice, immediately immersing us in secrecy and resentment. Roderigo and Iago discuss Othello’s recent marriage to Desdemona. Iago reveals his bitterness at being passed over for promotion in favour of Cassio and admits he follows Othello only to “serve my turn upon him”. From the outset, the audience knows that Othello’s supposed “honest” ensign is plotting against him.
Iago and Roderigo wake Brabantio to tell him that his daughter has eloped with Othello. Their crude, racist language (“an old black ram is tupping your white ewe”) exposes the deep prejudice in Venetian society and encourages Brabantio to see the marriage as monstrous and unnatural rather than loving. Already, Othello’s race and outsider status are being weaponised against him.
Othello, however, initially appears calm, dignified and confident. Brought before the Duke and senators, he must defend both his marriage and his reputation. He explains that Desdemona fell in love with him through the stories of his life as a soldier and traveller, not because of witchcraft. Desdemona herself speaks up, choosing her husband over her father and insisting she go with him to Cyprus. By the end of the act, the Senate decides that Othello must lead the defence of Cyprus against the Turks. As the characters prepare to leave Venice, Iago is left alone to outline his plan: he will ruin Othello by making him believe that Cassio and Desdemona are lovers. The seeds of jealousy and destruction are planted.
Act 2 shifts the action to Cyprus, a more chaotic, militarised setting that mirrors the emotional turmoil to come. A storm destroys the Turkish fleet, meaning the external threat to Venice is effectively over. However, Shakespeare replaces this military danger with a psychological one: Iago’s plotting becomes the real “war” of the play.
Othello and Desdemona arrive safely, and for a brief moment we see their happiness and mutual affection. Iago, however, immediately begins reading innocent behaviour in a poisonous way. He notices Cassio taking Desdemona’s hand and interprets this polite gesture as “framed to make women false”. To the audience, Cassio’s gallantry is harmless; to Iago, it is the perfect tool to feed Othello’s future jealousy.
That night, during the celebratory drinking, Iago encourages Cassio to drink more than he should, fully aware that he cannot handle alcohol. He then manipulates Roderigo into provoking Cassio, and a brawl breaks out. Othello is furious that order has been disturbed and removes Cassio from his position as lieutenant. Cassio is devastated, lamenting the loss of his “reputation”, while Iago pretends to comfort him, cleverly advising Cassio to ask Desdemona to plead his case with Othello. This seems like friendly advice, but in reality it sets up the central misunderstanding of the play. Iago closes the act with another soliloquy in which he vows to turn Desdemona’s “virtue into pitch”, using her kindness to destroy her.
Act 3 is the structural and emotional turning point of the play, often called the “temptation scene”. At the start of the act, things still appear relatively stable. Desdemona promises Cassio that she will speak repeatedly to Othello on his behalf. Her persistence in pleading for Cassio is sincere and generous, but it provides Iago with the exact material he needs to suggest that their relationship is more than friendship.
Iago begins his psychological assault subtly, planting doubts in Othello’s mind and then pretending reluctance to speak. Through half-finished sentences and hints, he presents himself as a loyal servant who is hesitant to accuse anyone outright. He famously warns Othello to “beware, my lord, of jealousy”, which has the opposite effect and only intensifies Othello’s suspicions. Othello, already sensitive about his age, race and status as an outsider, becomes increasingly insecure.
The dropped handkerchief becomes the crucial symbol of the act. Desdemona accidentally loses it and Emilia, trying to please her husband, gives it to Iago. Iago then arranges for it to end up in Cassio’s possession, providing the “ocular proof” Othello demanded. Iago also claims that Cassio has talked in his sleep about Desdemona, further fuelling Othello’s imagination. Overwhelmed by jealousy, Othello’s language and behaviour change dramatically: the measured, poetic general becomes fragmented and violent in his speech, swearing revenge. He kneels with Iago and swears to kill Desdemona, while Iago is promoted to lieutenant. By the end of Act 3, Othello’s trust has shifted fatally away from his wife and towards Iago.
In Act 4, Iago pushes Othello from suspicion into outright madness and brutality. He torments Othello with vivid sexual images of Desdemona and Cassio until Othello is driven into an epileptic fit. This physical breakdown shows how deeply jealousy has infected him; the once composed general is now completely destabilised.
Iago then sets up a cruel scene where Othello secretly watches him talking to Cassio. Iago steers the conversation so that Cassio laughs about his relationship with Bianca, but Othello, listening from a distance and misreading the situation, believes they are mocking him and discussing Desdemona. When Bianca appears with the handkerchief, Othello sees this as proof of Desdemona’s infidelity. Iago has created a situation in which Othello’s interpretation feels convincing, even though it is entirely false.
Othello begins to mistreat Desdemona openly. In front of Lodovico, he strikes her and calls her a “devil”, shocking the onlookers who knew him as a noble soldier. In private, he interrogates both Desdemona and Emilia, but refuses to accept their insistence on Desdemona’s innocence. Iago, meanwhile, continues to manipulate Roderigo, persuading him that killing Cassio is necessary if he wants to win Desdemona. Iago persuades Othello not to poison Desdemona, but instead to strangle her in the marriage bed – a choice that makes the murder more intimate and disturbing. By the end of the act, the death of both Cassio and Desdemona has been planned, and Othello believes he is acting as a righteous avenger rather than a deluded murderer.
Act 5 brings the tragic consequences of Iago’s scheming into full view. The act opens with the attempted murder of Cassio. Roderigo ambushes him in the dark but fails to kill him and is himself wounded. Iago, needing to cover his tracks, secretly stabs Roderigo and pretends to be the first on the scene, playing the loyal soldier once again. Cassio survives, which later becomes crucial for revealing the truth.
The central scene of the act is the bedroom murder. Othello enters while Desdemona sleeps and, in a chillingly calm manner, tells her he must kill her for her supposed betrayal. Desdemona pleads her innocence and asks for more time, but Othello is unmoved. Convinced he is carrying out a kind of twisted justice, he smothers her. Even as she dies, Desdemona remains loyal, attempting to protect him by claiming she has killed herself.
Emilia arrives, discovers the crime, and refuses to stay silent. She bravely confronts Othello and exposes Iago’s involvement, revealing that she stole the handkerchief at his request. The web of lies unravels rapidly: Cassio’s survival, Emilia’s testimony and Iago’s behaviour all point to his guilt. In a final act of cruelty, Iago kills Emilia when she refuses to be quiet, showing that he is prepared to murder even his own wife to protect himself.
Once the truth is undeniable, Othello realises the full horror of what he has done. Confronted with his actions, he delivers a final speech in which he attempts to shape how he will be remembered, asking to be described as one who “loved not wisely, but too well”. He then takes his own life beside Desdemona. Iago is arrested but refuses to explain his motives, maintaining his eerie silence. The play ends with order being tentatively restored: Cassio is put in charge of Cyprus and given the task of deciding Iago’s punishment. However, the emotional devastation remains, and the audience is left questioning how easily trust, prejudice and manipulation can destroy even a great man.
Ultimately, the play exposes the destructive power of jealousy and the dangers of a society built on rigid ideas of honour, gender and race. Othello’s tragedy is that he comes to see himself through the eyes of a racist, patriarchal culture and acts accordingly, believing that murder can somehow restore his damaged reputation. By the final scene, there is no sense of triumph in his death, only a haunting awareness of how easily a “great” man can be undone. Shakespeare leaves the audience with a world in which the truth is discovered too late, the innocent are dead, and the chief architect of the tragedy refuses to speak. In this way, Othello endures as a powerful study of trust, identity and the terrifying speed with which love can be corrupted into violence.