Macbeth Act 3, Scene 2
Lady Macbeth enters asking if Banquo has left the palace yet. Learning that Banquo is gone but will return again tonight, Lady Macbeth sends the servant to tell her husband that she wishes to speak with him in private. The servant goes to bring the king to his wife. Lady Macbeth feels that if her husband does not enjoy his royalty, then all of their deceit and treachery has been for nothing. If he does not seem happy, it would have been better if they had not killed the king to take his throne in the first place.
When Macbeth enters the room, she asks him why he is still thinking about Duncan when nothing can be done to revive the murdered king. "Things without all remedy / Should be without regard: what's done is done." Act 3, Scene 2, lines 11-2 Macbeth responds that they have not yet finished securing his throne and they are not yet safe. He says that Duncan lying quiet in his grave has it better than Macbeth who lives in fear and guilt after murdering the king. Lady Macbeth asks him to at least fake cheerfulness at dinner that night so that his guests will feel at ease and suspect nothing. He promises his wife that he will pretend to be happy and at ease and tells her to play up to Banquo and to speak well of him so that no one will suspect the malice that both Macbeth and his lady feel toward him. Macbeth's only comfort is that Banquo and Fleance can be killed. He warns Lady Macbeth that before the night is over another terrible deed will be done, but he does not tell her of his conspiracy to kill Banquo and his son. Night begins to fall around the castle.