Othello, the Moor, a general in command of the Venetian garrison, returns to the island having defeated the Muslim fleet. It is evening and a storm is raging at sea. On the shore the frightened crowd watches a ship battling against the waves and realizes that it is the general ’s. Everybody prays for his safety. When Othello appears on the bastions, announcing victory and danger overcome, the crowd cheers him enthusiastically. The only people who do not participate in this rejoicing are Roderigo, who in vain loves Desdemona, Othello ’s beautiful and faithful wife, and Iago, the older soldier, who hates Othello and is plotting against him for having promoted Cassio captain instead of him. The soldiers gather outside the inn to drink and sing. Iago manages to get Cassio so drunk that he ends up drawing his sword and wounding Montano, Othello ’s predecessor in the government of Cyprus, who had dared to reprimand him for his conduct. Meanwhile Iago foments a riot, until Othello hears the tumult and intervenes to quell it. After dismissing Cassio from his service, the general orders everyone to leave and remains alone with Desdemona. As the sky clears, they recall the early days of their love and walk arm in arm to the castle.
A hall in the castle. Iago sets his plot in motion by convincing Cassio that he will soon be captain, if he can persuade Desdemona to plead for him with her husband. Having told Cassio to wait for the lady in the garden, Iago reflects on his fate and on his faith in an evil God, on the cynical nature of men. Othello approaches and Iago begins to instill doubts in his mind about his wife’s fidelity. Othello has seen Cassio and Desdemona talking in the garden, but his fears are dispelled when his wife is joyfully received by women, girls and sailors who offer her trinkets. Othello is joined by Desdemona in the hall. When she takes Cassio’s side and asks her husband to restore him to the rank of captain, Othello flies into a rage. Desdemona tries to wipe his forehead with a handkerchief, which he had given her in token of his love, but Othello throws it onto the floor. Emilia, Iago’s wife, picks it up and Desdemona begs her husband to forgive her for having upset him. Iago tells Emilia to give him the handkerchief and not to mention it again. Othello, alone with Iago, feels his certainties crumble and asks him to help find proof of his wife’s infidelity. Iago deceives him by pretending he has heard Cassio talking in a dream to Desdemona and begging her to hide their love. The Moor’s last doubts are dissolved when Iago confides to him that he has seen one of Desdemona’s handkerchiefs in Cassio’s bedroom. Deeply shaken, Othello swears to get his revenge.
The great hall of the castle. A herald announces the arrival of Venetian ambassadors. Iago outlines his plan to Othello: he will bring Cassio to him in such a way that he, from a hiding-place, will be able to overhear his words and intentions. Desdemona enters, and attempts once again to defend Cassio’s cause. Othello asks her to show him the handkerchief he had given her, and unleashes his anger and resentment upon her until she is forced to go out. Alone, Othello gives vent to all his bitterness and jealousy. Iago appears and advises him to hide because Cassio is approaching. By a trick he gets Cassio to show the handkerchief which he had found in his house and which he believes to be a token left there by an unknown lover. Othello is by now definitely convinced that his wife has betrayed him. The sound of trumpets and a canon shot announce the landing of the Venetians. Cassio goes off and Othello informs Iago that he has decided to kill those guilty of betrayal. He names Iago captain and receives the ambassadors. When he reads the Doge’s message summoning him back to Venice and appointing Cassio as his successor, Othello – again incited by Iago – loses control and insults his wife in public, cursing her. Alone now, Othello collapses in a swoon. While in the distance can be heard acclamations in honor of the Moor, Iago basks in his triumph and gazes scornfully at the man he has ruined.
Desdemona’s bedroom. In her bedroom, Desdemona bids goodnight to Emilia after telling her the sad story of the handmaiden Barbara, abandoned by the man with whom she had fallen in love. Then she kneels and prays to the Virgin in preparation for sleep. Othello enters by a secret door, approaches the bed, contemplates Desdemona and kisses her three times until she wakes. Confronted with her husband who condemns her for her guilt, Desdemona proclaims her innocence, but in vain. Othello suffocates her without listening to her explanations. Emilia discovers the murder and cries for help. The Venetian ambassador, Iago and Cassio run to the scene, Cassio having just escaped ambush by Roderigo. When at last Othello discovers Iago’s trick, he bids farewell to life. In despair at having killed his innocent wife, he stabs himself and dies on Desdemona’s body, after kissing her lips for the last time.
