The plot of Macbeth is a tragedy. It follows the story of a Scottish general named Macbeth who receives a prophecy from three witches that he will become king. Driven by his ambition and encouraged by his wife, Macbeth murders King Duncan and takes the throne. However, his guilt and paranoia lead to a series of murders and ultimately his downfall. The play explores themes of ambition, power, guilt, and the consequences of one's actions.