We're looking at a very tricky character analysis here, because a character like Batman has all kinds of permutations, including two other movies with the same director and Christian Bale in the part. Getting at the heart of Bruce Wayne in this movie means ignoring most of the other Bruce Waynes out there, along with their delightful psychological scars.
In this case, we've skipped over the origin story: how little Bruce became the big bad Bat and why he chooses to do what he does. (That was in Nolan's first film, Batman Begins, and you really should give it a look if you want to tackle this one.) Most people know the basics: his parents were gunned down in front of him, leaving him with stupidly huge amounts of money and a burning desire to pummel senseless every criminal he finds. Naturally, he can't do that if everyone knows who he is: hence the coy disguise and the oodles of Q-branch goodies designed to give him the edge over the felonious hordes of Gotham.
And why dress like a bat? To scare the bejesus out of them. "Criminals are a superstitious, cowardly lot," he famously said in the comics. "My disguise must be able to strike terror into their hearts." Or, to quote Christian Bale in Batman Begins, "Bats frighten me. It's time my enemies share my dread."
The fact that bats actually scare Bruce Wayne is solely the purveyance of the Nolan movies. We're just stating that for the record, so you can see how easy it could be to make assumptions about this character that actually don't appear in the movie.
Those are the basics. As The Dark Knight opens, Bruce has been at it for a couple of years, with a staggering amount of success. The street-level scumbags are literally running scared, and the mob bosses creep around like mice afraid of the cat. Clearly, Bruce's unorthodox tactics are working.
And it does look like tactics, rather than something more personal. The pain that drove him to scamper around rooftops in the dead of night is still there, but it's deeply hidden under the minutiae of the task at hand. It's a big task. Small wonder that he talks about his gear and methods with Alfred instead of his dead parents. "Batman has no limits," he says, which is the closest he gets to talking about his underlying drive. The rest of the time, it's all "I need new armor" this and "those vigilantes are gonna get themselves killed" that.
There's a good reason for that: he doesn't want to be Batman forever. He's looking for a final victory, something that will let him hang up the tights for good and settle down with some nice girl (if not Rachel, then perhaps a certain raven-haired kleptomaniac with a similar animal fetish). This breaks from a lot of the earlier incarnations of Batman, when he was in it for the long haul. It also suggests that maybe he's less unhinged than he is elsewhere: someone who envisions an end game other than lying dead in the street with some gloating scumbag standing over him with a smoking gun.
That's vital as far as this movie goes, because it gives him a goal to work for. In fact, he's almost reached it. Crime is way down, citizens feel hopeful, and this Harvey Dent guy looks like just the sort to finally put the ball in the end zone. He tells Rachel:
BRUCE: You know the day that you once told me about, when Gotham would no longer need Batman? It's coming.
He's looking for an exit strategy and with Dent, he may have found it.
From a dramatic standpoint, there's really nowhere to go but down here. Either he puts the bad guys away and completes his mission (boring) or some really serious wild card enters the mix. Enter the Joker, there not only to destroy all of his hard work, but show him how pointless that work was. Just as he's getting ready to grab the big brass ring, he suddenly finds himself pushed to the breaking point by someone who can push his buttons like a deranged chimp.
So the test becomes one of resolve: seeing how far Bruce is willing to go to defend his efforts, and watching what happens when he has to make the toughest possible choices. Who's he gonna save? Who's he gonna let go? What happens when people around him start dying for his mistakes? And if he kills the Joker and saves all of those unnamed future victims, does that simply make the Joker's point?
Bruce gets plunged into a psychological sharknado, one so bad that it breaks his ally Harvey Dent in half and kills his only friend, Rachel Dawes. We can see how deeply it affects him, slumped in his penthouse in despair after Rachel dies, hesitating when Alfred admonishes him to be the outcast, and finally embracing a giant, horrific lie just to keep his city safe. And we know how much he loses in the process.
The thing he, he's still the hero. He not only endures, but he finds a way to keep his city safe. "I have one rule," he tells the Joker in the interrogation room, and for all the exploding hospitals and ferries full of hostages and cackling clowns saying mean things on the TV, he never, ever breaks it.
More importantly, he keeps his faith in the people of Gotham, trusting them not to blow each other up on the ferries and seeing his faith rewarded. Unlike Harvey, he doesn't snap. He shoulders his burdens and renews his commitment to the whole flying-around-on-rooftops-in-the-dead-of-night thing… all while making sure the Joker finally gets the padded cell he deserves.
Nolan mixes that with another, darker truth. Even though Bruce is a hero, he can't save everyone, a lesson he has to learn the hard way when Rachel gets killed. The other casualty? His reputation as a good guy. He doesn't kill anybody, but he takes the rap for all the people Harvey's killed: absorbing that heinous spiritual mojo so that the city doesn't lose its soul.
And Bruce, being Bruce, doesn't flinch. With a look of supreme realization on his face, he tells Gordon:
BRUCE: I killed those people.
If the good guys are going to win, they need to let him take the blame and vanish, leaving the city he loves safer at the cost of his own safety and reputation. He lies (or at least he lets Gordon lie about him) and in making that compromise, he preserves the practical effects of his victory. Granted, he also proved the Joker's point that no rule is sacred, but he also said he only had one rule… and taking the blame for killing someone is a long way from actually killing that person yourself.
Thus does Big Bruce experience what real defeat might feel like, and still finds a way to snatch victory from its grinning red jaws.
"I'm whoever Gotham needs me to be," he tells Gordon at the end, which is as potent a statement of sacrifice as you're likely to hear. Just a short while earlier, he was looking at hanging up the cape and cowl for good. Now he's lost everything—his girl, his reputation, even his ability to cruise around in that awesome Batmobile every night—for the good of the city he loves.
His sacrifice actually means a whole lot more because he wants to give it all up. We see what's waiting for him at the end, we sense that he wants a happy ending just like everyone else does. That he chooses to give it up hammers home how Nolan views heroes in worlds as dark as this one. The good guys can't always close the deal, Bruce tells us. Sometimes the dark forces really do overwhelm us. But there's always a way out. There's always a way through. And you can usually find it by putting other people above yourself. Bruce loses a lot by the end of the film, but he knows what that buys his city. And this is a guy who's always ready to pay the price.
We hear a couple of seriously gruesome stories about the Joker's origins in this film, all delivered by the man himself and all of them complete poppycock.
If I'm going to have a past, I prefer it to be multiple choice," he tells Batman in The Killing Joke, which is a sneaky way of saying we don't know who the heck this guy is. The authorities can't figure out where he comes from, we never see any secret hideout or scummy apartment belonging to him, and friends? As Maroni puts it, "have you met this guy?!"
All of which is a big way of saying we have no idea who the Joker is or how he got to be, um, that way. We only know him through what he does, and a guy this sick and twisted tells us volumes by his actions. We first see him robbing a bank, but even there, he seems to be about more than just a chunk of change. He's ripping off a mob bank, for starters, and as we eventually see, he's happy to light his giant piles of money on fire once he has them.
Then there's the fact that the entire robbery seems to serve as some kind of ultra-violent performance piece. He induces all the other robbers to kill each other off, then reveals himself as the last man standing as a sort of "ta-da!" to the hostages in the bank. You can almost hear him yelling "Get it? IT'S A JOKE!" to his unwilling audience leaving those dead bank robbers laying hither and yon as a sick little punchline.
The intention there, as it is throughout the film, is to cause a little panic and fear. He tells Two-Face,
JOKER: I'm an agent of chaos.
He really, truly means it. Rules bother him a lot, which means that doing anything predictable or expected is an absolute no-no. And there's more than freelance anarchy going on there. He hates rules because he sees how often people break them: how little things like morality and civilized behavior are chucked out the window when people start to get really scared.
In short, he's on a mission… a mission to show the people of Gotham City that they are every bit the monsters that he is. He pushes them into abandoning every principle they hold, he shows them how little the police or the Batman can do to keep them safe, and then he sits back and waits for the city to tear itself apart.
That guides all of his actions: not money or power so much as turning Gotham City into one big lunatic asylum. He wants to drag them down to his level, to show them how horrible they can be when they get pushed. It never happens, of course, but oh my does he come close. In that sense, he really is a terrorist: he doesn't have any goals that anyone can understand beyond anarchy for anarchy's sake.
And we're not really sure how he makes his plans. We don't see him marking up a big map of Gotham, or chortling with his henchmen the way they did back in the Adam West days. His schemes are pretty complicated, and seem to involve a lot of preparation beforehand (those charges ain't gonna set themselves). On the other hand, planning sounds like something that really annoys him, to the point where he vehemently defends it in his argument with Two-Face.
JOKER: Do I look like a guy with a plan?
He grins sarcastically, and considering that he's wearing a nurse's skirt, it's hard to argue with him.
If it's true, that would mean that he's some kind of idiot savant, connecting the dots in the strangest way possible and riding the ensuing tidal wave like the Big Kahuna himself. He's got a general sense of the chaos he's going to cause, and an ingenious way of doing just what he needs when he needs to in order to destroy any semblance of civilization around him.
That's the likely answer, but like a lot of things about the Joker, we're never going to know for sure whether he really is a spur-of-the-moment guy or whether his argument with Harvey was just more hot air. In the end, it probably doesn't matter. It only matters how wildly successful he is at bringing everything—everything—thundering down around everyone's ears.
He doesn't leave the bad guys out of the fun either. They're an organization, after all, and you've already seen how he feels about organization. When he first crashes their "little group therapy session," he arrives like the Devil himself, there to collect all the naughty little children and take them away.
His contempt for the underworld springs both from his disdain for their goals, and for the fact that they think they can control things the same way Dent and the cops do.
"This city deserves a better class of criminal," he sneers at one of the city's big crooks, and he really means it. The havoc he wreaks with them, to the point of burning down a giant pile of their money, doesn't leave them with anywhere to stand. They're in disarray just like the cops are, leaving panicked crowds and one very cranky Batman in the place of structure and order.
That, in the end, is all he really wants. And if he ever learns what Bats and Commissioner Gordon have to do to stop him, he'd probably just laugh his creepy little head off. The only thing that keeps him from total victory is Batman himself: who proves that Gotham has a soul and, against all odds, never breaks his one rule.
And the Joker is so twisted that the idea actually fills him with glee. In his own sick way, he kind of loves Batman. He even says so in the interrogation room, where he mocks Tom Cruise's "You complete me" line from Jerry Maguire. He can't imagine life without Batman to test, over and over again until one of them cracks. "I think you and I are destined to do this forever," he cackles at the very end, suggesting a lifetime of Batman thwarting the Joker's latest apocalypse by the skin of his teeth. That's about the scariest thing we've ever heard of, and we're betting the clown couldn't be happier about it.
We'd be remiss not to mention the fact that Heath Ledger—who won an Oscar for his role in the film—died before the movie came out. Whether or not that helped the film ratings is debatable, but, uh…it did.
Harvey, Harvey, Harvey Dent. What's there to say about him except that he so perfectly embodies his own phrase?:
HARVEY: You either die a hero, or you live long enough to see yourself become the villain.
That's pretty cold, Harv, but you gotta admit: no one goes from good guy to bad guy like you do.
And that's kind of the point. At his worst incarnations in the comics, Two-Face was pretty goofy: committing crimes based on the number two, like robbing the 2nd National Bank. That wouldn't do for Nolan's down-and-dirty Batman, so he's been reinvented here with a focus less on the literal and more on the symbolic. Harvey really does seem to be two different people in this movie. At first, he's the heroic District Attorney, ready to stare down mob assassins in the courtroom even as he's sending up their bosses for life.
Everyone loves Harvey. Even Bruce, whose squeeze Harvey's taken, is ready to give up being Batman because he thinks the DA is just that darn cool.
Then, of course, there's the other side. Once the Joker drives him over the edge, Harvey Two-Face is everything that Harvey Dent wasn't: violent, erratic, relying literally on chance to make all his choices, and ultimately a danger to children and other living things. Like that coin he constantly flips, Harvey has two distinct and opposite sides, and the tragedy of his character is that the dark side ultimately gobbles up the light.
But things in Harvey's psyche aren't quite the neatly split Oreo they might appear to be. There's always a little bad in Harvey's good, a touch of shadow in the midst of his light.
He's a bit of a sneak for starters. He doesn't mind bending the rules when it suits him; minor ones to be sure, but certainly notable. Look at how he pulls strings to get Rachel into that swanky restaurant, for instance, or how he knows that his convictions will be overturned in 18 months, but goes ahead anyway because it will buy the cops the time they need to do some real good. Sure, he has noble goals there, but the law he claims to uphold isn't always at the top of his mind.
Then there's his temper. Sweet merciful McGilligutty, is his cork in tight; when it pops, look out. He keeps it more or less under control, but every now and then, you can see it slip out. Look at him bellowing "YOU CAN'T GIVE UP!" after Batman says he needs to turn himself in. His voice is raspier, his forehead vein is throbbier, and suddenly that squeaky clean DA doesn't look all that different from the monster he becomes.
So clearly he's got some anger issues, which finally overwhelm him as Two-Face.
You can see the roots of that in Dr. Jekyll and Mr. Hyde (which Batman's original creators Bob Kane and Bill Finger based the character on), and that always makes for a cool character. It's an easy and very slick way of talking about everyone's dark side, and how the better angels of our nature constantly battle with the dark side. Harvey's stuck between those two halves. Unlike Batman, who ultimately stays on the heroes' side, and the Joker, who's rotten to the core, Harvey stands on the middle of a great big spiritual balance beam.
That makes him closer to us normal folks than either of the other two. Most of us try to be good and want to be good, but are tempted to do bad because we get angry or scared or some combination of the two. Harvey's us in the story, at least before he falls. After he falls, he's much more of a cautionary example: warning us folks in the real world who think that our anger and our fear can solve our problems.
We see that not only on an individual scale, but on a social scale as well. As a society, we're constantly asking ourselves—debating, arguing and in some cases screaming at each other—about whether we're doing the right thing, about whether we're keeping our country safe, about where the line between good and evil is, and if we'd even know that line if we saw it. That's true for a nation as much as plain old folks just doing their best to get through life. Harvey, a public official who's supposed to represent all of the people, makes the perfect representation of that. Have we fallen the way he has? Or will we stick to the light side and keep that manky evil from scabbing up our face? Harvey made the wrong choice, but we don't have to… if we take a little wisdom from his example, that is.
Man, three leads like that and this movie still find time for Commissioner Gordon?
Take that, Tim Burton.
Like Batman himself, this version of Gordon got his start in Batman Begins, and like Batman, we pick him up here in the middle of his story. Originally, he was the one good cop in the bad town: the only guy who never took a payoff, and therefore the only guy that Batman could trust. Together, they seem to be making a run at crime in Gotham, with Gordon acting as the good cop while feeding Batman information that can help him nail the really scary guys.
In fact, his arc here follows Batman's almost perfectly. Batman gets to hang out on gargoyles and look all broody and menacing, but otherwise, the two are pretty close. Both start out the movie on top of the world, and both get thrown for the god-king of loops by a freaky guy in a purple suit.
Want more comparisons? We got 'em. Both of them rely on Harvey Dent to close the deal on Gotham's underworld, figuring that he's more pure than they are. Oh yes, Gordon bends laws too… and like Batman he's open about it rather than trying to hide it or deny it. When Harvey gets on his case about the dirty cops in his department, he fires back:
GORDON: I don't get political points being an idealist. I have to do the best I can with what I have.
He himself isn't corrupt, but he's got to rely on corrupt cops if he wants to get the job done. That pragmatism certainly saves him from ending up like Two-Face (and seriously, how scary a supervillain could Commissioner Gordon have made?). But once again, like his buddy in the cape, it doesn't save him from having to enter into a nasty bargain in order to hold on to the fruits of his idealism. He has to spread the lie that Batman killed all those people, hiding Two-Face's crimes and hoping that it's enough to keep the city's criminals all locked behind bars. The Joker pushes them just that far, and the good cop in Jim Gordon can't entirely stop some of that evil from sloshing over.
Gordon is Batman's stalwart ally to the end, of course, even buying into the whole "blame the vigilante for everything" plan, which bites them in the rear in the third movie, but that also shows us his capacity for loyalty, his hunger for justice, and his desire to protect the innocent: all the things that good cops are supposed to do. That helps him hold onto his soul at the end of The Dark Knight, and even redeem himself by the time the third movie rolls around.
And like Harvey, he's also something of an everyman: somebody we can connect to. Unlike Batman (and you'll never know how thrilled we are to finally draw a distinction between them), he doesn't live in a huge estate or drive Lamborghinis around the city. He's got kids, he's got a mortgage, he's got problems we can all relate to… and like Harvey, he's faced with either giving up everything that's important to him or risk seeing the city go down the spout.
That makes him a less cautionary example than Two-Face: someone we can look up to, even when he makes mistakes, and know that he's really acting in the best interests of all of Gotham. Heroes are made of such stuff, and Gordon doesn't need a pair of tights or a cape to do it. He's the guy we all should aspire to be, even when the chips are down and it might be easier just to let his team gun down all the clowns. (Whew! Glad he avoided that little disaster.)
As much as we hate to say it, this is pretty much a big boy's movie, and the major female character doesn't have a lot to do other than support her men and be brave in the face of a gruesome death. It's not cool, and we're glad to see superhero movies ramping up their act a bit with the likes of Catwoman and the Black Widow running around.
To be fair, Rachel Dawes isn't too bothered by it.
This fast-talking career gal has known Bruce since they were little kids, and what he does by night, she does in the brightness of day. She puts crooks away like her squeeze Harvey. She just does it with a little less psychosis and a lot more belief in the power of the law. That makes her purer than either Harvey or Bruce, though to be fair she neither watched her parents die in front of her nor got to listen to the person she loved the most die while gasoline put the sizzle on her face.
To a certain extent, Rachel represents everything that's good about Gotham City. She's able to keep Bruce's secret without entirely condoning it and she reminds Harvey that he's not nearly as slick as he likes to think he is. That serves to balance their fervor with practicality, and to keep their feet on the ground even if they're swinging across rooftops with a cape billowing behind them. She's their rock, their weight, the firmament on which they stand. Without her, who knows what those two might be capable of?
Okay, scratch that. We know exactly what they might be capable of, since she gets blown up by the Joker's bomb midway through the film. Bruce's grief overwhelms him, but doesn't stop him from doing what he has to do (that's why he's the hero) while Harvey uses it as an excuse to do what his nasty temper has always told him he should do. When she dies, a little bit of them dies with her, and like the rest of Gotham, their souls come a little closer to pure madness.
You may have noticed something else here. Rachel's role in the story is defined by her relationship with men. On her own, she doesn't have any qualities other than "ethical lawyer" and "nice girl who can keep a secret." This is what people are talking about when they say women characters don't have a lot to do. When your most important dramatic moment is to die horribly just so your fiancé can go on a coin-flipping rampage of revenge, it kind of diminishes little girls' ability to find something relatable in you. None of that is Rachel's fault of course, but considering that she's probably the Caped Crusader's only real friend, we'd like to have seen the movie give her a few more cool things to do.
In simplest terms, Alfred Pennyworth is the reason Bruce never shows at the hospital with weird cuts and bruises.
He's Bruce's butler, manservant, and stalwart Man Friday: there to cover the legwork required to get him all that snazzy gear, and to stitch up those dog bites with competence and panache (a past as a combat medic will do that for you). If Bruce needs it, Alfred's got it, handy when you're taking on the kind of problems he does.
But Alfred is more than just a guy to press the cape and change the linens. He acts as a father figure to Bruce, and frankly to Rachel too: giving them advice and being there to support them when they need someone to lean on. He can give them a good talking to if they need it, and he's always ready with a sharp quip to remind them that they're not invincible.
BRUCE: Targeting me won't get their money back. I knew the mob wouldn't go down without a fight, but this is different. They crossed the line.
ALFRED: You crossed the line first, sir. You squeezed them, you hammered them to the point of desperation. And in their desperation they turned to a man they didn't fully understand.
BRUCE: Criminals aren't complicated, Alfred. We just need to figure out what he's after.
ALFRED: With respect, Master Wayne, perhaps this is a man that you don't fully understand either.
In the end, he loves them as much as any parent could and fills up that void left by the Waynes' death as well as any man ever could. This doesn't differ much from most other depictions of Alfred out there (though The Dark Knight makes him a cockney working man rather than a snooty aristocrat, to better fit actor Michael Caine's persona). Neither does the way his caring for his charges leaves him making decisions that he shouldn't.
This happens most notably when Rachel gives him a letter to give to Bruce, one that tells Bruce she's going off with Harvey and will never be with him romantically. (Not unreasonable, considering his nighttime hobbies.) Alfred chooses to burn the note after Rachel dies, in order to spare Bruce the pain. We certainly know why he does it: as the resident father figure, he wants to spare his "son" any more agony. Rachel is gone, he reasons, and her motives don't matter anymore. Better to keep that from Bruce than pour salt in an already throbbing wound.
As we said, it's a noble sentiment, at least in theory. In practice, though, it turns out to be a big, bad mistake (though we don't know how big until The Dark Knight Rises four years later). In the first place, it instills a false belief in Bruce that Rachel would have been with him, something that keeps him from healing and moving on. More importantly, it denies Rachel the weight of her choice. She's going to be with Harvey, that's the end of it, and she needs him to understand and respect her choice. By burning up the letter, Alfred takes that away from her—the last decision she ever made—and tarnishes her memory in the process.
But this, too, is a lot like a parent. Parents mean well, but they mess up sometimes and in their effort to keep their children safe, they usually make them even more vulnerable. Poor old Alfred falls into that trap, right when Batman himself is making a similar mistake. For all the good things he does for Batman, he lets him down in the way that matters most. Bruce and Alfred are closer together than they thought: making the same mistakes at the same time for the same reason. It tinges their steadfast relationship with something a little more tragic, and if you tune into The Dark Knight Rises, you can see the ways that failure comes back to haunt them both.
Fox has a much larger role here than he does in the comics, where he usually just runs Wayne Enterprises while Bruce pummels criminals by the light of the moon. Here, he's kind of Bruce's Q Branch: using Wayne Enterprises money to deliver all kinds of gadgets that Bruce finds ever-so-useful. From a plot standpoint, he answers the practical question of where Batman gets "those wonderful toys" (to quote an earlier movie), as well as demonstrating that Batman can't be Batman without a solid team to back him up.
From a personal perspective, they kind of have a fun vibe going. Lucius knows that Bruce is Batman, and Batman knows that he knows, but they never talk about it directly… though they do talk about it a lot. So it's all hidden phrases and double meanings and winking at each other in the boardroom, instead of Bruce just coming out and saying "I need a cooler Batmobile, buddy." "Three buttons is a little 90s," Lucius smirks at Bruce when he asks about a new suit, knowing full well that he's looking for an entirely different kind of suit.
It's weird seeing that kind of playfulness in a movie so serious, but that's the way their partnership has evolved. Lucius is properly grateful of course—Bruce saved his job and made him the head of his company back in Batman Begins—and since he knows what Bruce does with all the high-tech goodies spilling out of the lab, he must feel pretty good about his place in the universe. No wonder he and Bruce have fun-filled conversations that no one else gets. They're teaming up to put Gotham's scumbags behind bars! Woo-hoo!
At the end of the day, however, Lucius serves a more important role that just filling out the monthly batarang quotas. Like Rachel, he knows where the line between right and wrong is, and he's there to tell Bruce exactly when Batman's crossing it. His take on Bruce's cell phone surveillance system?
LUCIUS: This is too much power for one person.
Luckily for him Bruce agrees, turning the machine over to Lucius and letting Mr. Fox destroy it once the Joker is safely trussed up. Like Rachel, Lucius is good at reminding Batman that he can't live long enough to see himself become the villain, and Batman is smart enough to take the lesson to heart.
The Scarecrow's really just a cameo here—he got his chance in the spotlight in Batman Begins—but we get a little reminder of what he can do at the very beginning of the whole thing. In the comics, Dr. Jonathan Crane was a psychologist who enjoyed studying the effects of fear, usually by putting on a truly hideous mask and spraying his victims with a panic-inducing drug.
He's still at it here, peddling his fear gas as a drug and finally getting sent back to Arkham Asylum as the movie opens. It tidies up a bit of plot from Batman Begins—which ended with Crane still on the loose—and further emphasizes that the Caped Crusader is seriously kicking butt. With Crane going back to jail, it seems like Gotham can finally sleep easy at night.
Crane also serves as another connection between The Dark Knight and earlier incarnations of Batman. The Scarecrow is one of the most famous members of Batman's rogues' gallery, having first appeared way back in 1941 and created by Bob Kane and Bill Finger just like old Bats himself. He's shown up in other media too: notably in old cartoons like The Superfriends and newer ones like Batman: The Animated Series, and in the show Gotham where we get to see him as a very troubled teenager. Murphy is here to hold up that end, and quietly remind us that there's a whole lot more bad guys out there than the Joker himself.
Mr. Lau is what we politely refer to as a "plot device." He's venal and corrupt, and even as a gangster he's kind of bland: keeping the underworld's money for them without doing any of the more exciting gangster stuff like running underground casinos and arranging for the violent deaths of various rivals. For most of the movie, he exists only as a kind of macguffin: there just to give everyone something important to chase after instead of being an actual personality on his own.
That changes after the Joker finally gets hold of him and sets fire to him sitting atop a literal mountain of money. He turns from an incredibly dull gangland figure into a larger symbol of Gotham's underworld. When Batman starts his crusade against crime, the criminals in Gotham look a lot like him: a little tougher and meaner maybe, but pretty garden variety as criminals. Batman gets to work and starts putting these guys away, but in their place, a freak show is being created, and they rise up to fill the vacuum.
Hence the Joker takes this guy and burns him up to let the world know that business as usual is over. "This city deserves a better class of criminal," he snarls as the money lights up behind him, and with it, the dull Mr. Lau exits the play: a walking, talking symbol of Gotham's fading business-as-usual bad guys.
Sal Maroni serves the same basic purpose that Mr. Lau does. He's part of the old order, picking up where his former boss Don Falcone left off when Falcone was carted off to the nuthouse halfway through Batman Begins. He's part of the old guard: non-flamboyant gangsters who used to run Gotham like kings and who now find themselves running for their lives ahead of Batman and DA Harvey Dent.
Maroni himself is venal, corrupt and awfully darn sure of himself. Even when Batman drops him off a roof and breaks his legs, he walks around with a self-satisfied smirk on his face. Sadly for him, his days are numbered, and ironically he has no one but himself to blame. He and the rest of his buddies ultimately hire the Joker to kill the Batman, and in the process, start the last stage of their inevitable replacement.
Fitting too that it's Two-Face who does him in. The guy who worked so hard to put Maroni behind bars as a good guy now has a remarkably easy time killing him as a bad guy. And if Maroni hadn't hired the Joker, Harvey never would have become Two-Face. Enjoy the irony as your car crashes, Sal: it's all on you.