The witches gather around a boiling cauldron in a cavern as a storm rages outside. They stir their concoction while chanting spells. When Hecate appears, she praises their efforts. Macbeth arrives and demands the truth about the prophecies. The witches offer to let Macbeth hear the truth from the mouth of their master and he accepts. A series of spirits and apparitions appears before Macbeth. The first warns him to “beware Macduff [and] beware the thane of Fife” (4.1.73-73). The second tells him that he cannot be killed by any man born of a woman. The third tells him that he is safe until a forest named Birnam Wood comes to Dunsinane Hill. The final vision is of eight ghostly kings, the last of whom carries a mirror. The ghost of Banquo appears behind them. When Macbeth calls on the witches to tell him what the vision means, they dance and vanish, leaving Macbeth to ponder what he has seen. Lennox arrives to tell Macbeth that Macduff has already fled to England. Macbeth decides to send the murderers out to capture Macduff’s castle and to execute his wife and children.