In a thunderstorm, three witches decide to meet again on the heath "after the deed is done." Next, a captain reports to King Duncan that Macbeth beat Macdonwald in battle. Ross adds that the Thane of Cawdor was traitorous to Scotland during the battle. The three witches confront Macbeth and Banquo on their way home from the battle. They predict that Macbeth will be King of Scotland, and Banquo, though never king himself, will beget rulers. The witches leave and Ross informs Macbeth that he has inherited the title Thane of Cawdor (as also predicted by the witches). Macbeth contemplates the prediction of him being king, and wonders if he should help make it happen. Malcolm reports to King Duncan that Cawdor admitted his traitorous deeds at his execution. The king then warmly greets Macbeth and Banquo. To Macbeth's dismay, King Duncan declares his eldest son, Malcolm, Prince of Cumberland (i.e. the next king). At Inverness Castle, Macbeth's wife learns of his encounter with the witches and decides that she'll persuade Macbeth to fulfill his destiny through foul play. She then learns that King Duncan is coming to her castle to stay the night, strengthening her decision to murder Duncan. Macbeth appears and his wife tells him she'll do the foul deed herself. Duncan arrives and Macbeth tells his wife he doesn't want to murder Duncan. She talks him into it, adding that they'll frame Duncan's own guards with the murder.

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