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The main theme of the play is Macbeth, the play's leading character and tragic hero. A clear idea develops, an ambition difficult to achieve: the desire for power, which leads to destruction not only for himself, but for others. Basically, once Macbeth's ambition is aroused, his desire for the throne of Scotland leads to his own destruction as well as to many others featured in the play.

Because of his overwhelming desire for the throne, He first turns into a liar,then a murderer, and finally, a cruel and oppressive ruler (tyrant) which Scotland suffers from. His actions have directly resulted in the death of King Duncan, Banquo, Lady Macduff, her children and servants, Siward, and finally, his own death.