In the main role of the Marquis he proves to the world that his Oscar win for Shine was no fluke. And it is time for him to prove it. Prove it he does with an unbelievable performance littered with a buffet of emotive range, everything from playful to painful, and all done with a little smirk. He shows the side of the Marquis that is admirable. He doesn t just show him as a madman but instead as a tortured artist hell bent on writing.
True writers write because they have to, they have no choice.
By taking away his ability to write the Marquis descends into madness. If he had been allowed to write his recovery would have eventuated. Wait a second lets start over. Quills is the story of the Marquis De Sade. That much, I am sure you can gather.