Macbeth is a tragedy by William Shakespeare. Three witches tell the Scottish general Macbeth that he will be King of Scotland. Encouraged by his wife, Macbeth kills the king, becomes the new king, and kills more people out of paranoia. Civil war erupts to overthrow Macbeth, resulting in more deaths. The play's main themes are loyalty, guilt, innocence, and fate. All deal with the central idea of ambition and its consequences