- Macduff's soliloquy: Macduff expresses his fear and suspicion of Macbeth, and his determination to act against him. He says, "O Scotland, how does this brother's war affect thy manly courage? Can such things be, and overcome us like a summer's cloud, without our special wonder?" He also refers to Macbeth as a "tyrant" and a "butcher."
- The witches' prophecies: The witches' prophecies, which Macbeth has interpreted as promises of power and security, begin to turn against him. The witches' prediction that Banquo's descendants will be kings suggests that Macbeth's line will not endure, and that he will ultimately be defeated.
- The appearance of Banquo's ghost: Banquo's ghost appears to Macbeth at a feast, and his presence fills Macbeth with fear and guilt. The ghost is a reminder of Macbeth's crime, and it shows that he is not safe from the consequences of his actions.
- The news of Macduff's escape: Macbeth learns that Macduff has escaped to England to join forces with Malcolm, the rightful heir to the throne. This news further threatens Macbeth's power, and it suggests that he is losing control of the kingdom.
- The gathering of Malcolm's forces: Malcolm, with the help of Macduff and other Scottish nobles, begins to gather an army to march against Macbeth. This growing opposition to Macbeth suggests that his reign is coming to an end.