In honor of the upcoming The Dark Knight, and in the hopes that Heath Ledger's performance changes the way I look at the Joker forever, here are five key traits of Batman's world, according to Gavin. (Sources will be cited, but like Frank Miller's bat-universe, my bat-universe may diverge slightly from accepted continuity.)
1. Bruce Wayne is the mask. Batman is the real identity.
There are a number of sources for this idea, but the first place I heard it articulated was by Kevin Conroy, who did Batman/Bruce Wayne's voice for the Batman Animated Series. I would go a bit further and play with the idea of Bruce Wayne being just one of Batman's masks. There is some precedent for this in the comics: Matches Malone, Lefty Knox. Batman can be anyone, anywhere. Paranoia is at least as powerful as physical intimidation. The man you've worked with for years, your best friend, could be the Bat. The Bruce Wayne: Fugitive storyline also plays with the idea of a Batman without Bruce Wayne, and the Over the Edge episode of the Batman Animated Series provides another key to that door. Batman would still be Batman even if the Bruce Wayne mask were taken away.
2. Never during the day.
This is a throw-off line from Frank Miller's Batman: Year One, which writers ignore at their peril. The Bat doesn't make public appearances. He doesn't testify in court. The only time you will ever see him is when he takes you down or saves your life, and even then, only for a moment. The Bat only works as a secret, a rumor, a myth. The Bat can never be captured, tied up, or examined under light. The mask is flimsy, and the only way to keep someone from pulling it off is to wear it sparingly. Other masks (see #1) are more durable, and just as useful.
3. The utility belt has a finite number of pouches.
Batman: Year 100 has the best take on this. Making Bruce Wayne a man with unlimited resources is ultimately a mistake. Batman is interesting only in his limitations. No superpowers. The only available tools are what he can carry silently. In this spirit, there is no Batmobile. (Also see #2.) Batman does not travel in a marked car that stops at traffic lights and signals left turns. If he drives, it is in an unmarked car, without the mask. Motorcycles make more sense, since a helmet is a mask, but still only something plain and unmarked. Something that can be abandoned.
4. There is something deeply wrong with Batman.
Grant Morrison's Arkham Asylum is a good source for this. Batman can't be written as totally crazy, because the sense of right and wrong is so essential, but Batman is so hell-bent on rightness, on structure because of something missing inside of himself. He has to spend every moment of his life building order out of chaos because he doesn't have that order inside of him. Detective fiction is also instructional: Batman is obsessive/compulsive (look at his trophy room in the Batcave), and either a bit autistic or sociopathic. He can't forget and constantly has to organize the information in his head before he loses his place. He can't relate to people, but is a tremendous actor. He's jarringly detached, but he can never let go of anything.
5. Jason Todd
He was Robin. He died. He's dead. Bringing Jason Todd back was the worst decision a Batman writer has ever made, and that's saying a lot. The false Jason Todd in the Hush storyline is interesting. Jason Todd really being alive is not. Losing a Robin, and the guilt Batman feels (or doesn't feel?) about it is key to his character. His inability to stop using a sidekick is key, too. Hell, at the time she replaced Tim Drake, Batman didn't even like Stephanie Brown. Why do children keep seeking the Batman out, and why is he, the strongest will in the DC universe, unable to say no?