Don't worry; there are no spoilers here. [Be aware, though, of spoilers in some comments.]
There's been a lot of talk about The Dark Knight, whether it focuses on its box-office haul, its bleak tone, or (especially) Heath Ledger's astonishing performance as The Joker. It is a film, and performance, that demands to be pondered.
I'm no film critic, but I know what is riveting. I felt like some sort of addict watching Ledger. Whenever he was off-screen, I wanted him back. When he came back, I felt slightly sick and scared shitless.
This is not a diary about actors or film craft. It's a diary about ideas.
Interestingly, The Dark Knight's predecessor, Batman Begins, mentions the power of ideas. Henri Ducard (played by Liam Neeson) presages both Batman and The Joker in the following quote:
A vigilante is just a man lost in the scramble for his own gratification. He can be destroyed, or locked up. But if you make yourself more than just a man, if you devote yourself to an ideal, and if they can't stop you, then you become something else entirely.
"You must become more than just a man in the mind of your opponent," Ducard intones. "You must become an idea!"
In The Dark Knight, The Joker is an idea. Reviews of the film have frequently equated him with terrorism. Manohla Dargis, writing in the NYT, demurs that "He isn't a terrorist, just terrifying." The Joker's brutal actions, she asserts, have "no rhyme and less reason." He is the horrifying idea of chaos itself.
In The Dark Knight, chaos means the absence of rules. The Joker asks: "Do I really look like a man with a plan? . . . I just do things. I'm a wrench in the gears. I hate plans. Yours, theirs, everyone's." He's clear who he is not. "I am not a schemer. I show schemers how pathetic their attempts to control things really are."
And this, finally, is why I am scared shitless in the movie theater. In my small way, I've always attempted to control things. Perhaps you have, too. Perhaps you've tried to stave off panic by acquiring information, by asking questions. Perhaps you've worked harder than you really needed to because you feared the alternative. Perhaps you've tried in vain to "control" your world as a loved one lay dying of an uncontrollable disease.
So when The Joker tells a major character the following:
You were a schemer. You had plans. Look where it got you. I just did what I do best-I took your plan and turned it on itself.
you feel a little sick because you've made plans too. You've often wondered "where it got you." Sometimes you've felt like someone, or something, was turning your plan "on itself."
The Joker represents, in bold and disturbing relief, the chaos that we fear and try to avoid even in our quiet moments. He is unabashed and unashamed. He glories in what we most fear. "I am," he says, "an agent of chaos."