In your coursework you should be aware of the story of Macbeth.
The play opens as three witches plan a meeting with the Scottish nobleman Macbeth, who at that moment is fighting in a great battle. When the battle is over, Macbeth and his friend Banquo come across the witches who offer them three predictions: that Macbeth will become Thane of Cawdor and King of Scotland, and that Banquo's descendants will become kings.
Banquo laughs at the prophecies but Macbeth is excited, especially as soon after their meeting with the witches Macbeth is made Thane of Cawdor by King Duncan, in return for his bravery in the battle. He writes to his wife, Lady Macbeth, who is as excited as he is. A messenger tells Lady Macbeth that King Duncan is on his way to their castle and she invokes evil spirits to help her slay him. Macbeth is talked into killing Duncan by his wife and stabs him to death. No-one is quite sure who committed this murder and no-one feels safe, but Macbeth is crowned king.
Now that Macbeth is king he knows the second prediction from the witches has come true, but he starts to fear the third prediction (that Banquo's descendants will also be kings). Macbeth therefore decides to kill Banquo and his son, but the plan goes wrong - Banquo is killed but his son escapes. Macbeth then thinks he is going mad because he sees Banquo's ghost and receives more predictions from the witches. He starts to become ruthless and kills the family of Macduff, an important lord. Macbeth still thinks he is safe but one by one the witches' prophecies come true, Lady Macbeth cannot stop thinking about Duncan, becomes deranged and dies. A large army marches on Macbeth's castle and Macbeth is killed by Macduff.
This is just the basic story and there are lots of extra characters and details you can include. However, do not fall into the trap of retelling the story in your essay - you will get no marks for it because the examiner already knows what happens. Instead, use the plot to support your work and ideas. Let's have a look at how you can do this next.