Summary: Act Four

Iago continues to torture Othello psychologically. He plants vivid description of Desdemona's alleged sexual activity until Othello blacks out.Iago then purposely place Othello in a place where he can see but not hear a conversation with Cassio about Bianca. But he tells Othello that the conversation is about Cassio and Desdemona. Othello witnesses Bianca comes in and throws handkerchief at Cassio, accusing he have another lady.

Lodovico arrives from Venice and inform Othello that he is order to return to Venice, and that Cassio is appointed at his place.Othello strikes Desdemona in Lodovico's presence, then rudely dismisses her, and leaves in a jealous rage. Lodovico expresses his astonishment at the change in Othello.

Othello questions Emilia about Cassio and Desdemona's relationship, acting as if Emilia is the mistress of a brothel and Desdemona one of her prostitutes. Othello denounces Desdemona to her face as a whore Desdemona turns for help to Iago, who reassures her.

Roderigo, protesting to Iago that his gifts to Desdemona have won him no favor from her, threatens to ask for the return of the gifts. Iago counters this treat by telling Roderigo that Desdemona will leave for Mauritania with Othello unless Roderigocan delay them. The best way to do this, says Iago, is by killing Cassio.

Othello walking with Lodovico, orders Desdemona to go to bed and to dismiss Emilia.As Emilia helps Desdemona prepare to bed, they discuss marital infedelity, with Desdemona arguing that no woman would be unfaithful to her husband and Emilia arguing that women have the same desires as men do.

Reference
Shakespeare, W. (1993). Othello. United States of America: Washington Square Press