The three witches are referred to by many of the characters as the “weird sisters”. Throughout the play they represent the temptation towards evil that every man has within himself. They play upon Macbeth’s latent ambitious desire for political power. They know his weaknesses and specifically target those in order to test his strength of character by tempting him towards evil. They feed upon the dark thoughts of Macbeth and get pleasure from the chaos that unfolds because of their prophecies. The mischief that they cause is a result of their supernatural powers as well as of their ability to understand human weaknesses.
While the other characters speak in blank verses, the witches on the other hand speak in rhyming couplets that often sound like riddles. Part of the reason behind speaking in rhyming couplets might be to hide the mischief and trickery in the crafty play of words. As such, their prophecies and predictions keep the audience at the edge of their seats until the very end wondering what exactly their words might mean. The rhymed speeches along with their weird potions and dance makes them seem slightly ridiculous. These elements give them a sort of caricatured appearance and make them seem comical. But despite all absurdity, the witches are tremendously powerful and extremely wicked. The bloodbath that follows in the play is a result of their manipulations, thereby clearly making them the most dangerous characters in the play.