Iago, Othello's ensign, wants to rise in the ranks. When Othello promotes Cassio to the position of personal lieutenant, Iago plots against Othello and Cassio. Othello elopes with Desdemona, the daughter of Senator Brabantio, and Iago realizes he has the perfect chance to get back at Othello. He asks Roderigo, a former suitor of Desdemona, to inform the senator that Othello has run off with his daughter.

When Turks threaten Cyprus, the Senate sends Othello to Cyprus to defend it and makes him the new governor. Not knowing that Iago was behind Brabantio's earlier protests of their marriage, Othello orders Iago to accompany his wife.

Roderigo goes along at the urging of Iago, who tells Roderigo that Desdemona will tire of Othello. Iago also tells Roderigo they must discredit Cassio to prevent Desdemona from running away with him. Iago gets Cassio drunk, then has Roderigo start an argument with him. Montano, the former governor of Cyprus, intervenes, and Cassio wounds him.

Iago then tells Othello about the fight and Othello fires Cassio. Iago tells Cassio he can regain his job by having Desdemona talk to Othello for him.

When Cassio presents his case to Othello's wife, she agrees to speak to her husband about it. When she does this, she only feeds Othello's jealousy.

Meanwhile, Iago's wife Emilia has found a handkerchief dropped by Desdomona which was given to her as a gift from Othello.

Emilia shows it to Iago, and Iago plants the handkerchief in Cassio's room and tells Othello that Desdamona has given Cassio a handkerchief. When Othello asks his wife for the handkerchief and she cannot find it, he becomes convinced that she gave it to Cassio and has been having affair with him.

Letters from the Duke of Venice arrive recalling Othello and naming Cassio the new governor. Desdemona praises Cassio.

For this, Othello strikes and berates her. Later, Othello goes back to the castle to murder his wife. Othello, still loving Desdamona, kisses her awake, asks her to prepare her soul for death, then suffocates her in bed. When Emilia tells Othello the truth about her husband Iago, Cassio backs up Emilia's story. Othello wounds Iago, then kills himself. Iago kills Emilia. After Iago is led away in chains, Cassio becomes governor of Cyprus.