Macbeth's initial crime is a product of opportunistic prophecies, a weakness of character, his "vaulting ambition," and certainly the influence of Lady Macbeth. Thereafter, he is compelled to commit further crimes in an attempt to cover his tracks and defy the three witches' prophecy. After Duncan's death and the flight of Malcolm and Donalbain, Macbeth reigns as king of Scotland until his death. The more power Macbeth gets, the more he will do anything to keep it. , "I am in blood Stepped in so far that, should I wade no more, Returning were as tedious as go o'er" (Shakespeare, 3.4. 142-144) Lady Macbeth likewise is initially obsessed with power: she wants to be queen but is corrupted by her own greed.