Act 4, As Iago, continues to manipulate Othello, Othello becomes more and more vexed. He falls into a trance of rage. Then, Iago speaks to Cassio while Othello speaks, and seeing Cassio smile, Othello has been pushed over the edge. He wants to kill Desdemona himself. He also orders Iago to kill Cassio. Then, when Desdemona mentions Cassio publicly, Othello slaps her, and she runs off. She still loves him though, being devout and true. Othello asks Emilia to change the sheets on the bed, and soon Desdemona knows she will die.