This scene is focused on the effects of Duncan’s murder on Lady Macbeth. Previously Lady Macbeth had supported her husband, driven by ambition and excitement. Now apparently guilt-stricken Lady Macbeth is exhibiting strange behaviour that the doctor and of Lady Macbeth’s gentlewoman have been tasked to keep an eye on her behaviour.
“Lo you! here she comes. This is her guise, and, upon my life, fast asleep. Observe her: stand close.” – Gentlewoman
“Out, damned spot! out, I say!” – Lady Macbeth