Act 5

Lady Macbeth - "Hell is murky!" (pg 206) - Hell is dark, as she sleep walks trying to get the imaginary blood off her hands
Macbeth - "The devil damn thee black" (pg 214) - The devil turn you dark, basically he's talking about how his servant has betrayed him
Macbeth - "to hear a night-shriek" - basically he's talking about how before an unknown scream in the dark would have frightened him

Act 5 is the end of Macbeth and Lady Macbeth. We see that Lady Macbeth has gone crazy from guilt. She wanders her castle at night reliving the night when she and Macbeth killed Duncan. She trys to wash the imaginary blood from her hands as she frets over what she had done and the imaginary scene she keeps seeing over and over again. Later in the Act we go to Macbeth preparing for battle he says "the devil damn thee black" or the devil turn you dark because his servants are abandoning him. He's basically calling them traitors. Macbeth by know has lost all sense of reason and fear thus the quote "to hear a night-shriek" he goes on to say he no longer feels fear. Thus his judgement is distorted which ultimately leads to his downfall when Macduff defeats him.