Iago is one of Shakespeare's most complex and heinous villains. The role he plays is rather unique and complex, far from what one might expect. Iago is the whole reason there is any conflict in the play "Othello" . If he never had entered the play, Othello would have married Desdemona and they would have lived happily ever after. Right from the beginning of the play to the very end he causes conflicts. He is directly or indirectly responsible for the deaths of: Othello, Desdemona, Emilia, and Roderigo. All of the problems he causes are through lies, treachery, manipulation, and a deep unknown hate. Some of his hate is fueled by jealousy and revenge. .
Iago deceives, steals, and kills to get everything that he wants. However, it is not that Iago pushes aside his conscience to commit these acts, but that he lacks a conscience to begin with. Iago's amorality can be seen throughout the play and is demonstrated by his actions. Iago is ingenious. He is clever and he is evil. In the eyes of others he is perceived as honest and trustworthy, but inside he is a sinister villain. Iago is an expert judge of people and their characters. He is able to manipulate the minds of people into performing actions that are advantageous to him. In the first scene of the play, Iago gives the audience warning that he is not all that he seems when he says, "I am not what I am." (I,i,65).
For someone to constantly lie and deceive one's wife and friends, one must be extremely evil or, in the case of Iago, immoral. Iago tricks Othello into believing that his own wife is having an affair, without any concrete proof. Othello is so caught up in Iago's lies that he refuses to believe Desdemona when she denies the whole thing. Much credit must be given to Iago's diabolical prowess which enables him to bend and twist the supple minds of his friends and spouse.
Iago also manages to steal from his own friend without the slightest feeling of guilt.