Macbeth decides to mention Banquo specifically in the toast, which prompts the re-appearance of Banquo's ghost. Macbeth again reacts to the spirit, much to the bewilderment of his guests. Lady Macbeth, afraid her husband is losing his mind and will reveal their crimes, bids the guests an abrupt goodnight and shuffles them out of the hall. When they are alone, Lady Macbeth, who is baffled by Macbeth's behavior, tells him that his lack of sleep is causing him to hallucinate. Macbeth insists that he must consult the three Weird Sisters to find out what dangers lie in wait. Macbeth and his Lady retire to bed and the scene ends with Macbeth's final thought that, because he is new to such heinous crime, his conscience is overactive, but he will improve
