Scene 1,2,3 and 4
These are very short scenes so I will go through them all quickly.
In the first scene, the Doctor and a Gentlewoman are waiting for Lady Macbeth, who the Gentlewoman has seen walking in her sleep, talking and writing letters. She emerges, talking about Banquos death and pretending to wash her hands. She has a light with her that she never leaves behind now. She talks about how her hands will never be clean, a stark contrast from the beginning, where Macbeth was saying the same thing and she was just acting like it was not a problem. She is going insane. The Doctor comments on how even resting, she is not allowed sleep.
In scene two, we meet all the traitorous lords who have ditched Macbeth to join the English army. They also mention the metaphor of how Macbeth’s secret murders are sticking to his hands. They are on their way to Birnam Wood.
In scene three we are back to Macbeth, in his castle. He says he is not afraid and that he will fight till he dies, something he thinks is impossible. He makes mention of how he doesn’t care that his lords have left, and of how all the cowardly soldiers on his side will be hanged.