In this scene they are situated, outside of Lady Macbeths castle many characters have shown up to have dinner with Macbeth and Lady Macbeth as their hosts. Duncan and Banquo compliment the castle of its pleasant smell and wooingly good look. In this scene Lady Macbeth is pretending to be nice and happy to see Duncan when really she is a serpent underneath. And the audience can relate to this as she told Macbeth herself to do this and she is demonstrating that she can do it very well as well.

Macbeth- Act 1, Scene 6.