Othello swears revenge, Iago swears to help. Cassio, Iago, Emilia comfort her. Cassio with Bianca, Cassio asks her to copy the handkerchief he found in his room. Iago twisting Othello in all directions, Othello collapses. Bianca brings in the handkerchief.
Messenger comes from Venice.
Othello strikes Desdemona in public. Othello questions Emilia, does not believe her. Othello confronts Desdemona. Iago and Emilia with Desdemona, various reactions. Iago kills Roderigo, accuses Bianca.