...half of Batman, at least, is his Rogue's Gallery.
So I have to take exception with the idea that the movie is about Batman. Batman is reflected through the villains around him.

That said, while Heath Ledger's performance was unfukwitable, I can't swear it's the definitive Joker (so far). I will not sleep on Mark Hamill in the animated series. I think he might have been the first performer to truly nail the Joker.

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