O Banquo, Where Art Thou?
Of course Macbeth is a Coen brothers movie. The Scottish play is essentially a caper: A criminal plot is hatched and executed, kind of like in Raising Arizona or Fargo. As in The Ladykillers — criminally overlooked, by way — the conspiracy goes off without a hitch just before the midpoint of the action, after which the pitiless hand of cosmic justice initiates a long and bloody rebalancing.
Source: washingtonexaminer.com