What's Gothic About Act One?

There are lots of Gothic elements in Act One of Shakespeare's Macbeth.

The Weird Sisters portray many such elements, such as the power of three, the fear of the unknown and the warping of human nature. They are uncaring as to human suffering and show no remorse, which are two major elements of human nature that separate us from being animals.  They embody the supernatural gothic element.

Lady Macbeth displays a twisted version of human nature and not one that is expected within a woman of her standing.  She is calculating, cold and ambitious, to the point where she plots the most high risk murder she possibly could in order to get money and power.  Her scathing attitude towards her husband and his human kindness creates a sense of fear within her, as he is not as constant and unchanging as she is due to his emotion.  She sees feelings as weaknesses and so is terrified that Macbeth's softer heart could ruin them both.  She emasculates him, possibly so as to keep herself fully in charge.  She has understood that she cannot be king of everywhere and so becomes ruler within her own territory.  There is an attitude within her that makes the reader think that perhaps if she had been born a man it would not only have been Scotland that would fall to her. (In my opinion, Lady Macbeth could have been Queen of the World had she just been born a bloke. King of the World. Whatever.)  She is also two-faced, and can act the picture of sweetness and light when required of her (when she is approached by a messenger in this act and when she pretends to swoon in the following act) but is actually the opposite.  This is Gothic in nature because this type of woman is unknown in the context of the story.