Kill Duncan and you can be the new trauma dep. leader!
Death of Two Surgeons
The beginning of Acts One and Two go into detail about the witches' prophecy for Macbeth. They claim he will be the ruler, and this prophecy lead him to power.
...and Two More
Macbeth, at the end of Act Two, was convinced to kill Duncan. The fact that he would murder someone shows how ambitious he was to have as much power as possible.
In Act Three Macbeth not only killed Duncan but his best friend. The need for power lead him to betray everyone that was close to him. Macbeth's ambition has tremendously grown since the beginning of the play.
Congrats Malcolm: New Head of Trauma!
Macbeth continued to add more people to the obituary in his quest for power. He took the life of anyone who he felt was a threat to him.
The final battle in Act Five is fought between Malcolm and Macbeth. The prophecies given to Macbeth (he could not be defeated by anyone born from a woman) gave him a false sense of hope that he could not lose. However, Malcolm was born from a c-section!
Malcolm defeated Macbeth at the end of Act Five! He now rules over the land/hospital because he saved the people from the terrifying reign of Macbeth.