Shakespeare opens the play in the city of Venice. It is a city that has created a reputation for robust commercial activities taking place as well as military might. There are several banks in Venice City and thee have helped to enhance economic performance of the city. It is early in the morning and two men have arrived at Brabantio’s house to deliver a message to him. The two men who have paid Brabantio a visit are Roderigo and Iago. Roderigo is a young man who had formerly sought after Desdemona for the marriage. He has been fairly successful in business and significant amount of money. Iago is an ensign who is bitter that he had been overlooked by Othello in a recent military promotion. The message that the two men are carrying is that Othello has eloped with Desdemona and the two are planning to get married.

In a quick conversation that is characterized by the use of words that have been selected carefully to infuriate Brabantio, Iago soon leaves the premises, allowing Roderigo to explain all the details that are related to the incident. By leaving early, Iago provide grounds that he could use to insulate himself in the event accusations arise concerning the issue. While feigning friendship, Iago meets Othello and informs him about the reaction of Brabantio to the news. Othello, Desdemona and Brabantio meet before the Duke of Venice where Brabantio accuses Othello of using magic to seduce his daughter. Othello defends himself by saying that he used legitimate means to seduce Desdemona. He says that he explained his adventures to Desdemona, upon which Desdemona is called to testify. Desdemona astonishes the senators by admitting before her father that she willingly agreed to marry Othello.

A conflict has arisen against the Turks and the Duke appoints Othello to lead the attack against the Turks. Upon the appointment, Othello must leave for Cyprus immediately. Desdemona requests the Duke to allow her to accompany her husband to Cyprus, a request that the Duke approves. Othello organizes for a ship to bring his wife during the next trip to Cyprus. During this time, Othello believes wrongly that Iago is still his friend and requests him to accompany Desdemona to Cyprus.

Iago provides a warning to Othello that there are rumors of the existence of a legal attempt to break his marriage. However, Othello takes confidence in the fact that he is militarily important to the City of Venice. With this in mind, Othello approaches the Duke together with senators with a lot of confidence. Due to a situation that that has arisen in Cyprus, Cassio has been sent to fetch Othello for a meeting. At this moment, Iago meets Cassio and informs him about Othello's marriage. In a little while, Brabantio and his party arrive. The rage on Brabantio's face is unmistakable. Brabantio threatens Othello with violence while at the same time accusing him of using sorcery to seduce his daughter. According to Brabantio, there is no way Desdemona can voluntarily marry Othello.

Reports coming from Cyprus indicate that there is an impending attack from the Turkish fleet. However, the reports differ with regards to the size of the Turkish military forces that are expected to launch an attack. Othello, Cassio, Brabantio, Iago and others get into a meeting. Noting the importance of the impending danger, the Duke quickly appoints Othello to lead a battle to defend Cyprus from the impending attack from the Turks.

The Duke takes notice of Brabantio. Brabantio says that his daughter has been seduced using a magic spell. Brabantio is of the opinion that there is no way his daughter could accept to marry the man. With these facts, the Duke promises to help push for the prosecution of the culprit. However, that is before the Duke realizes that the man in question is Othello. When he realizes this fact, he calls the general and asks him to defend himself. In a highly dignified and persuasive speech, Othello defends his relationship with Desdemona (76-93 and 127-169). Othello then requests the Duke to invite Desdemona so that she may testify. Iago together with a group of other men to fetch Desdemona. When Othello finishes his narration, the Duke appears to offer him support by saying that, "I think this tale would win my daughter too" (170). When the time comes for Desdemona to defend herself arrives, she speaks so eloquently and convincingly that she brings the debate to an end.  While Desdemona is still thankful and obedient to her father, she is now married, and her loyalty has shifted to her husband.

Having successfully dealt with this personal issue, Othello now has to attend to the more pressing needs to protect Cyprus. They are running out of time, and he has to depart immediately. Desdemona requests for permission from the Duke to accompany her husband, a request that the Duke readily accepts. Othello is supposed to leave that night, and that means he may not go with his wife. He asks Iago to come with Desdemona in the next ship. Additionally, Emilia, Iago' wife, is to accompany Desdemona and act as her maid. When Brabantio warns Othello that, "She has deceived her father and may thee" (289), Othello dismisses this idea and believes that Desdemona is faithful to him.

Iago and Roderigo have remained on stage. The outcome of the hearing has been devastating to him. He had hoped that the relationship between Othello and Desdemona would collapse, leaving him to take Desdemona. He says he should drown himself in the face of these humiliating circumstances. Iago rebukes Roderigo that his thought is silly and demonstrate misery. He advises Roderigo to go to Cyprus and wait until such a time when Desdemona would get bored with Othello. When that happens, Roderigo will take Desdemona. Iago finishes by promising Roderigo that he would help him get Desdemona. The only thing he needs to do is to carry lots of money.

From this scene onwards, all the actions take place in Cyprus. All the protagonists at the center of the initial conflict including Roderigo, Othello, Iago, Cassio, and Desdemona have all moved to Cyprus. It is now the center of the new battle. The Governor of Cyprus, Montano, has waited for the Venetian forces but they have delayed. A dangerous storm has hit the ship at sea and, that has affected the journey. In a little while, a messenger comes with the message that the Turkish ship has had massive damage as a result of the heavy tides in the on the seas. As such, Cyprus is no longer under threat from the Turks.  Cassio's ship is the first to arrive followed by Desdemona's. Upon arrival, the first question that Desdemona asks is concerning Othello. She is concerned the Othello has not arrived. Meanwhile, Iago is planning on the best way to approach Cassio in his treacherous plan.

Finally, Othello makes a triumphant entry. He, Desdemona and other characters move into the fortress as Iago stays behind to inform Roderigo that Cassio and Desdemona are in love. He does this to provoke a fight between Roderigo and Cassio, an event that would lead to a mutiny and in the long run cause Cassio to be pushed away from the fortress. In another soliloquy, Iago is again talking about his hatred for Othello. While the details are not very clear, it I evident that he plans to drive Othello mad.

During the celebration, Cassio is in charge of the drinking and feasting. He takes all his orders from Othello who informs him to tell the soldiers to drink in moderations and make sure that they are peaceful.  It is the responsibility of Cassio and Iago to enforce the orders of Othello. After issuing the instructions, Othello and Desdemona retire to bed. It is the first time that the two are sharing a bed after their marriage. Iago and Cassio have remained alone. Iago introduces the story of Desdemona to Cassio, but Cassio shows no interests. He, them, invites Cassio for a drink. Once again, Cassio shows no interest. It is after a lot of pestering that Cassio to drink alcohol with Iago.

While taking advantage of their drunken stupor, Iago drives Roderigo into starting a fight with Cassio. Other soldiers join the fight, and soon a huge brawl arises among the soldiers. Othello then sends Roderigo to ring the alarm bell. The alarm bell wakes up Othello and his soldiers, and he demands to know who had started the fight. Feigning reluctance, Iago names Cassio as the person responsible for the fight. Othello views this as indiscipline, and he relieves Cassio of his post. Together with Desdemona, the two return to sleep.

Iago uses his persuasive power on Cassio by urging him to speak to Desdemona to help him put up a strong a case before Othello. Cassio finds this to be a favorable idea and he agrees with the idea. Iago uses his wife who is as acting as Desdemona's maid to arrange for a meeting between Cassio and Desdemona.

Cassio holds a meeting with a group of musician and another countryman. He sends them to go and fetch Emilia from wherever she was. When Emilia comes, Iago sends him to go and get information regarding the conversation between Cassio and Desdemona. She comes back with the report that indeed there was a talk between Desdemona and Cassio. Desdemona listened and conveyed his message to Othello, who in return promises to reinstate him when the right time comes.

Cassio meets with Desdemona. He requests Desdemona to intercede for him with Othello so that he may get back his job. Knowing that Othello and Cassio have been long-term friends, Desdemona readily agrees to help. Desdemona promises to put up a strong defense for Cassio and help mend fens between the two of them. She hopes to convince Othello to recall Cassio. Othello and Iago enter the room where Desdemona and Cassio are having a conversation. Cassio, embarrassed because of the events of the previous night, embraces Desdemona and leaves the house. Iago, not one to let an opportunity fly away, makes an undermining comment that is meant to wind up Othello. He says, "Ha, I like not that." Desdemona introduces the discussion about the position of Cassio. Othello is in no mood for an argument and simply promises to talk with Cassio. However, it is notable that Othello is distracted by some personal thoughts.

Iago and Othello are in a discussion. Othello refuses that he is a jealous man. Iago speaks in a manner likely to suggest that he knows something, although he refuses to divulge the details. Othello appears very vulnerable when he denies that he is a jealous man. Doubt and suspicion have started creeping into his head. The statements of Brabantio have started getting better of him. Perhaps her father was right that the girl is deceitful and Othello needs to be cautious with her. As Iago leaves, Othello thinks seriously about his situation. He feels that he could have been tricked into marrying a woman whose heart is already on another man or men. He must wipe this woman away from his heart! But he wishes that he is wrong about this thought.

When Desdemona reenters the room, Othello has changed drastically. Everything about him has changed. He looks keenly at Desdemona, perhaps to look out for any signs that could be indicative of her activities. When Desdemona goes to wipe him with the handkerchief, Othello pushes it away, and it falls. When Othello and Desdemona go for dinner, Emilia goes and picks the handkerchief that her husband has always told her to take. She plans to have a copy of it, but Iago takes it from her before that happens.

When Othello reenters, Iago readily notices that he is troubled. He looks weak, and his speech is also fevered. Othello believes that his wife has been having a secret affair. Savagely, Othello turns to Iago, and he demands to see the proof of Desdemona's infidelity. This is the moment that Othello has been waiting for. He explains that during the night, Cassio kept turning, talking and embracing Desdemona while he cursed Moor. To hammer his point home, Iago tells Othello that he has seen Cassio wipe his face with a handkerchief embroidered with strawberries. Othello readily recognizes the handkerchief as he one that he had given to Desdemona.

Othello is now certain about his wife's infidelity. Doubt and suspicion have been supplanted with incontrovertible proof. While he is dismissing love, Othello calls for vengeance. Things are never going to be the same between him and Desdemona. Othello wants Cassio dead. Iago agrees with him. However, he is left wondering how he can kill Desdemona.

Desdemona has sent for Cassio. She wants to tell him that she has talked with Othello and that all the plans are under to reinstate him. However, Desdemona has realized that she cannot find her handkerchief. Othello enters and says that he is feeling as if he is suffering from a headache. He requests specifically for the strawberry-embroidered handkerchief to tie around his head. However, Desdemona deflects this question and continues to ask about Cassio. Othello gets agitated and leaves.

Cassio has found the handkerchief in his lodgings, but he does not know the owner. He presents it to his mistress, Bianca, to make a copy of it. Just them, Bianca realizes that the handkerchief belongs to a woman and she accuses him of having another affair. Iago had placed the handkerchief in his lodgings.

In a conversation with Cassio, Othello hears that Cassio has confessed to sleeping with Desdemona. Upon hearing this, Othello becomes weak and collapses. In a little while, Cassio enters the room and Iago explains that Othello has always had epilepsy and the seizures are quite common. Iago makes the decision not to try to revive Othello, instead of letting fit to take its course. He then instructs Cassio to leave the building and come later. Othello regains his conscience, and he starts saying weird things. Then, Iago sees Cassio approaching and tells Othello to pull himself and hide so that he may hear the manner in which Cassio is talking about his venture with Desdemona.

Just as Iago has indicated to him, Othello withdraws, not knowing that Iago is manipulating him. However, he has become emotionally involved to a level that he is willing to anything as long as there is a promise that it would give him relief. Cassio and Iago are talking about Bianca. From a distance, Othello can see Cassio smiling and laughing, although he does not hear what they are saying. Othello gets to believe that Cassio is talking about how much Bianca loves him. In the middle of the conversation, Bianca enters the room. She is holding the handkerchief in her hands. She takes the handkerchief and throws it at Cassio. The moment Othello sees the handkerchief in the hand of Cassio's mistress is the moment he sees the proof of what he has always suspected. He has confirmed Desdemona's infidelity, and both of them must die, tonight.

Othello approaches Emilia and questions her about Desdemona's infidelity. Emilia says that there is nothing immodest that has taken place between Desdemona and Cassio. Instead of believing that nothing has happened between Desdemona and Cassio, he feels that Desdemona is so cunning that she has influenced Emilia to deceive hide her misdeeds. While they are in private, Othello approaches Desdemona and threatens her with banishment from the castle. He refers to her as a whore. Desdemona immediately denies these charges.

When Emilia comes in, Othello leaves immediately. While it is evident that Desdemona is exhausted out of these accusations, she, however, does not understand her crimes. Emilia, on her part, believes that there is a villain character that has stirred up Othello's sense of jealousy to cause trouble in her marriage.

Roderigo makes an appearance in a conversation with Iago. Roderigo says he has been exhausted in her desire to capture Desdemona. Thus, he seeks to pull out. In furtherance of his plot, Iago tells Roderigo that he needs to kill Cassio to prevent Othello from being sent elsewhere, thereby allowing Desdemona to stay in Cyprus. Roderigo is convinced that the idea is good.

It is after supper and Othello orders his wife to go to bed. Besides, he also tells her to fire her maid. As Emilia and Desdemona discuss these developments, Emilia feels that Desdemona, after all, may have married the wrong man. There is a strange feeling to Desdemona that she may die. If happens, she asks Emilia to wrap her body in her bedsheets which are already on the bed. Desdemona sings the ‘willow song' as a reminder of a situation similar to hers in which maid Barbary went mad and disappeared. Desdemona dies singing this song. Desdemona will die while singing this song.

It is in the streets at night. Roderigo and Iago are planning to kill Cassio. As Cassio draws near, Iago instructs Roderigo to attack him. When Roderigo attacks, he is unsuccessful, and Cassio stabs him.  On seeing the unexpected turn of events, Iago approaches and stabs Cassio in the leg. He runs way leaving Cassio writhing in pain while crying uncontrollably. When Othello hers Cassio cry, he believes that Iago has undertaken the job and executed it accordingly. In return, Othello must harden his heart and spill his wife's blood on the same bed on which the things he was betrayed.

This is probably one of the most absorbing scenes in the entire play. Othello walks into their bedroom as Desdemona sleeps. He walks very calmly into the room, knowing that time has come for her to die. Desdemona calls upon him to join her in bed. Othello responds coldly that Desdemona needs to pray and confess all her sins. It is at this money that Desdemona confirms her earlier feelings that she is about to die. She is devastated knowing that she is innocent from the accusations that Othello has levelled against her. Since Desdemona feels that there is nothing more which she can do to prove her fidelity, she can only weep and cry. She asks Othello to banish her, or even give her a little more time to live, but that is unacceptable at this time. Othello stiles Desdemona, presumably using a pillow.

A group of people including Montano, Gratiano, Iago and others rush to the bedchamber where Emilio is crying. Immediately they arrive, Emilio gets mad at her husband. She accuses him of orchestrating all these things. In response, Iago says that Desdemona was indeed unfaithful. Emilio narrates how her husband had asked her to steal the handkerchief and the manner in which he planted it at Emilio's residence. Realizing he is exposed, Iago stabs Emilio and runs away. At this point, Othello realizes that he has been manipulated, tricked and misused. He now realizes that Desdemona had been faithful to her all the time.

Iago is caught and brought for questioning before Othello and Cassio. Iago refuses to say a thing, saying his mouth will stay shut forever. Upon noticing that Iago will not give away any words, Othello asks the group to remember both his good points and the bad as "one that lov'd not wisely, but too well." Othello stabs himself, collapses on the bed and dies. Othello's death creates a power vacuum. Lodovico has taken charge of proceedings in this case. He takes Othello's property and hands it over to his next of kin, by marriage, Gratiano. Cassio becomes the commander and will sentence Iago appropriately. Lodovico is scheduled to carry back the bad news to Venice.