He that filches from me my good name
Robs me of that which not enriches him
And makes me poor indeed.
Othello, a Moor general in the Venetian army, has secretly married his beloved Desdemona, daughter of Venetian Senator Brabantio. He has also promoted Cassio to be his lieutenant, which infuriates Iago, who was expecting the promotion for himself. Iago becomes obsessed with revenge, and determines to use Desdemona to achieve his goals.
Othello is sent to Cyprus by the Duke of Venice, and Desdemona joins him, bringing Emilia, her lady in waiting, with her. Emilia also happens to be Iago's wife. Once in Cyprus, Iago successfully stains Cassio's reputation by getting him drunk and encouraging a fight that leads to Cassio's arrest and demotion. At Iago's prompting, the deeply remorseful Cassio begs Desdemona to plead his case to her husband, Othello, so that he might return to his service.
Iago then plants the seed of doubt in Othello's mind that Desdemona may be unfaithful to him with Cassio. When Desdemona does then plead the demoted soldier's case, Othello's suspicions are aroused. To further Othello's paranoia, Iago acquires a handkerchief of Desdemona's (a treasured gift from her husband) and arranges to have it planted in Cassio's possession.
His jealousy and rage encouraged, Othello instructs Iago to kill Cassio while he violently confronts his own wife. Despite Desdemona's claims of innocence, Othello is convinced of her infidelity and strangles his wife in her bed. When Emilia discovers the body, she refuses to believe her husband could be so evil as to manipulate Othello to murder. But as the truth reveals itself, Emilia reports the events of the tragedy—despite Iago's violent attempts to stop her. Faced with the shame of having murdered an innocent Desdemona, the tormented Othello stabs and kills himself. A furious Iago murders his own wife, and must then face the justice of the Venetian state.