Lucas got his old film school teacher Irvin Kerschner to render the
central and darkest segment of the original trilogy. This is where the
Star Wars tapestry came together: the good guy rebels lose at every
turn, while a key revelation rocked the world, instigating many a
primary schoolyard brawl. Lawrence Kasdan added depth and contrast to
Leigh Brackett's script, elaborating the hero's journey and Freudian
angst that make the Luke / Darth Vader dynamic so compelling. There is
real emotion in the SFX-saturated mix that leaves you breathless -
after Godfather II, it's the 2nd most cited example of a sequel better
than the original.