In Shakespeare's tragedy of the imagination, Macbeth and Lady Macbeth are doppelgangers: they both are seduced by ambition and become obsessed with advancing themselves; the preternatural affects them; the phantasmagoric realm of witchcraft, insomnia, and madness conquers them. The difference between Lady Macbeth and her husband is that her candle of life burns more violently and goes out much more quickly.
In order to portray her character, then, the actor must convey an exigency in her character. Here are some ideas:
- In Act I, Scene 5, Lady Macbeth reads her husband's letter and immediately determines that she must intervene in his plans and act as a fulcrum for his ambition because she fears that he is "too full o' th' milk of human kindness." Therefore, being eager for Macbeth to be king, she decides to "pour spirits into [his] ear." That is, Lady Macbeth decides to talk Macbeth out of any misgivings he has about going after the crown.
- Then, in a very character-revealing soliloquy, Lady Macbeth calls upon the preternatural world to unsex her, making her more masculine (violent). In this scene, she must be portrayed as slightly obsessed with the plan to take the crown from King Duncan even if it means that she changes to a masculine form.
- Later, in Act I, Scene 7, when Macbeth arrives and has misgivings, Lady Macbeth cruelly challenges his manhood, saying he looks "green and pale," describing how she would rip a baby from the nipple if she "had so sworn as you/Have done to this." She impresses Macbeth with her warrior cruelty that he orders her to "Bring forth men-children only" and he tells her he is now convinced.
- Just as quickly as she has seemed almost fiend-like, Lady Macbeth transforms herself into the gracious hostess when the guests arrive at the castle.
- That night as the Macbeths plan the murder of King Duncan in Act II, Macbeth thinks he sees a dagger before him and hears a bell inviting him toward his dastardly deed. So, too, does Lady Macbeth enter the realm of the phantasmagoric as she imagines "the fatal bellman" in the shrieking of an owl. Further, she cannot kill Duncan because she feels that he resembles her father. (Here is a hint that Lady Macbeth does not possess fully the bravado she thinks she has. At this point, she shows signs that she can break.)
- But, her resolve is again with her because when Macbeth returns in Act II, Scene 2, imagining blood on his hands because he is haunted by his crime of regicide, Lady Macbeth is again her cruel self, deriding Macbeth, "A little water clears us of this deed:/ How easy is it then!" (This is dramatic irony here as later she repeatedly tries to wash her hands of the blood of Duncan.) It is important to stress this scene.
- In Act III, Scene 2, Lady Macbeth still has her resolve to appear as though they have nothing to do with Banquo's death. But Macbeth is worried because Fleance lives. His wife consoles him, saying that Nature's lease is not eternal. Later, in Scene 4, she does a good job of allaying the apprehensions of their guests who wonder what has come over Macbeth as he sees Banquo's ghost:
...My lord is often thus,
And hath been from his youth. Pray you, keep seat.
Then, she chides her husband, "Are you a man?"
- It comes as a surprise to audiences that after her stoic behavior Lady Macbeth has become insane in Act V, Scene 1, but she has been weaker than she has imagined herself. Her behavior is obsessive: she imagines blood upon the stairs and in her tragic imagination, she feels compelled to wipe out these stains that seem to reappear. Paranoia and the phantasmagoric haunt her as she relives the murder of Duncan:
Out, damned spot! Out, I say! One: two: why , then, 'tis time to do 't. Hell is murky. Fie, my lord, fie!...What need we fear who knows it?...Yet who would have thought the old man to have had so much blood in him? (5.1.)
(Lady Macbeth is frenetic, twisting each way, tortured by her imaginings. Her mind exhausts her with its horror. She is disheveled, and there is a torturous despair in her eyes. She collapses.)