Desdemona's handkerchief, Othello Playbill by Garfield Shakespeare Company.
Othello is Shakespeare's saddest play.
He's an older military man, and he's black. She's a young white woman of noble birth. Othello and Desdemona marry in secret, and, with impressive bravery and devotion to each other, the couple attain the begrudging acceptance of Desdemona's father and the council of her home city of Venice.
But the way is not cleared for Othello and Desdemona to have a life together. Machinations and plots against them are afoot from the beginning. Enter Shakespeare's greatest villain: Iago.
"I hate the moor," he says. Why? Does Iago resent Othello's success and position because he's black? Is he jealous of Othello? Is he in love with Othello? Is there some other reason for him to ruin these people's lives? Whatever his motives are, he never reveals them.
Iago's mysterious hatred of Othello makes him fascinating, but his understanding of human psychology makes him dangerous. Especially his particular genius for spotting and exploiting any weakness in those around him.
As Iago weaves his net "to enmesh them all" we look on in horror. We want to scream at Othello: Don't believe him! He's deceiving you! But a well-placed stolen handkerchief convinces Othello beyond a doubt that Desdemona is unfaithful and, for the sake of honor, has to die.
The tragedy of Othello and Desdemona is that they were not destined for failure. They were caused to fail by an outside force, deliberately, and disastrously.
Iago's manipulation is so masterful and so complete that he makes Othello forget what he once knew:
"For she had eyes and chose me."