Scene 1: Banquo thinks to himself that Macbeth has done something wrong to become king. Macbeth hires murderers to kill Banquo and Fleance to stop Banquo's prophecy coming true.
Scene 2: Macbeth tells Lady Macbeth that Banquo now needs to be killed. Lady Macbeth wants to convince him otherwise, but now Macbeth keeps his evil plans to himself, no longer trusting her.
Scene 3: Banquo is killed by the murderers. Fleance escapes.
Scene 4: Macbeth is holding a large meal in honour of him being new king. The murderers tell him Banquo is dead but Fleance escaped. Macbeth then sees Banquo's ghost at the meal when no one else can. Lady Macbeth sends him to bed so he doesn't say anything to make him seem guilty.
Scene 5: The three witches meet again discussing Macbeth.
Scene 6: Lennox, Malcolm and Macduff all suspect Macbeth to be evil, calling him a tyrant. Malcolm and Macduff are making plans in England.