The Cypriots are awaiting the arrival of Otello, the governor of Venice, whose ship is battling a storm. The storm subsides and Otello lands, to the joy of the crowd. Only Iago and Roderigo do not share the general happiness. Iago is bitter because Otello has named Cassio his lieutenant instead of Iago; Roderigo is in love with Desdemona, Otello’s wife. Iago and Roderigo get Cassio drunk and provoke his duel with Montano. Otello dismisses Cassio from his service and orders Iago to restore peace. When silence has finally been restored, Desdemona and Otello declare their love.
Iago advises Cassio to ask Desdemona to intercede with Otello for the disgraced officer’s pardon. He tells Cassio to wait for Desdemona in the garden
where she usually rests with her maid Emilia, Iago’s wife. Alone, Iago unveils his beliefs: God is cruel and a man was created in his image. Otello sees Cassio with his wife, and Iago plants the seed of jealousy, which grows as Desdemona pleads with her husband to forgive Cassio. Desdemona drops her handkerchief, and Iago takes it from Emilia. When Iago and Otello are alone, he tells how he heard Cassio talk in his sleep about Desdemona,
and that he saw Desdemona’s handkerchief in Cassio’s hand. Otello vows vengeance. His glorious life now seems to have disappeared like a dream.
Desdemona again broaches the subject of Cassio, and Otello openly accuses her of adultery. He demands the handkerchief he first gave to her. Desdemona fails to find it. Otello spies on the meeting between Iago and Cassio, who displays a handkerchief he has found in his room. Otello cannot hear the dialogue, but the sight of the handkerchief convinces him. He cannot restrain his jealous fury and publicly insults his wife. Iago feels that his triumph is near.
Desdemona is preparing for bed. She sings a sad song about unhappy love, then prays and goes to bed. Otello enters and warns her that he has come to kill her. Desdemona protests her innocence, but he refuses to believe her and strangles her. Emilia knocks, then bursts in to tell Otello that Cassio has killed Roderigo, who according to Iago’s plot attacked him. Desdemona moans, Emilia cries for help. Iago’s villainy is revealed. Otello kills himself over Desdemona’s lifeless body.