Here is a brief plot summary of Othello:
Iago manipulates Cassio to make him drunk and gets Roderigo to draw him into a street fight. Iago has his revenge on Cassio when Othello strips Cassio of his rank for misbehavior. Then Iago decides to make Othello believe his wife is unfaithful. He encourages Cassio to ask Desdemona to plead with Othello to be reinstated. Iago suggests to Othello that Desdemona is Cassio’s lover. Trusting Iago, and mad with jealousy, Othello promotes Iago and asks Iago to help him kill Cassio and Desdemona.
Iago plants Desdemona’s handkerchief in Cassio’s room. Cassio gives it to his mistress, Bianca. Othello believes Bianca’s possession of the handkerchief is proof that Desdemona and Cassio are lovers. He verbally abuses his wife in front of others, who are shocked at the change in the noble and powerful man.
Iago has manipulated Roderigo into trying to kill Cassio. The attempt goes wrong, and Cassio wounds Roderigo; Iago stabs Cassio in the leg. Othello hears Cassio cry out and thinks Iago has killed him. He returns home, ready to kill Desdemona. Meanwhile, Iago “finds” the wounded Cassio and accuses Bianca of causing Cassio’s injury. Iago quietly kills Roderigo and sends Emilia (Iago’s wife) to Desdemona with news of what has happened.
Othello reaches the sleeping Desdemona first. He kisses her, wakes her, and accuses her again. Over her protests that she loves him and is innocent, he smothers her. Emilia enters and Desdemona revives for a moment, declaring herself guiltless but saying, as she dies, that Othello is innocent of her death. Iago and others enter, and Emilia defends Desdemona’s innocence, recognizing that Iago is behind the tragedy.Othello sees the truth and tries to kill Iago. Iago kills Emilia and flees; Othellocondemns himself and commits suicide. Iago is seized and taken away.