The 'Dark Knight' trilogy consists of Bruce Wayne's struggle to restore order to his world, a struggle embodied by five villains he must defeat.
According to Will Brooker, author of Batman Unmasked: Analyzing a Cultural Icon, "The defining characteristic of Gotham must be that there is always crime. Because Batman is, on one key level, the man who fights crime." Which might sound trite, but Gotham City is, within Christopher Nolan's trilogy of films—Batman Begins, The Dark Knight, andThe Dark Knight Rises—the crucible in which Batman's soul is forged. In the video below from Jack's Movies Reviews, it's argued that the five villains Batman faces off against each represent an aspect of the caped crusader that he must integrate successfully in order to save both the city and himself.
After the death of his parents, young Bruce Wayne's world was thrown into darkness and disorder. He retreated from his life, fled Gotham, and attempted to lose himself in the chaos of a violent world. This storytelling device can be found in stories going back thousands of years. One such example is Hamlet, where the Prince must confront his father's murder and decide whether to avenge his parent's death. In his case, it doesn't work out so well, but it's not a 1:1 correlation.
If Bruce Wayne was to remain removed from the city, not only would there be no story, but the character would stagnate and die an inner death. It's only when he returns to Gotham in Batman Begins, after having confronted his worst fears in the bat cave, that he is able to begin the process of saving both his soul and the soul of the city.
Scarecrow = Fear
First, Wayne needs to "accept fear. Only then will he have the internal strength needed to defeat the monster." However, just as the citizens under the influence of Scarecrow's weaponized gas view that villain as a monster, they also see Wayne, who has turned himself into what he feared most (a bat/creature of the night) as a monster as well. By facing his fears, Wayne's worst fear—the sound rejection by his beloved Gotham—becomes a reality. In the process, the character learns that the struggle he has undertaken is not really about himself, but about Gotham, and for that he must fight selflessly.
"The chaos of the world doesn't care about any rules, and in order to be successful, he needs to fight chaos."
Ra's al Ghul = Order
While Wayne seeks to establish order within his life and city, Ghul feels that Gotham is beyond saving, and so it must be destroyed and rebuilt from the ashes. Wayne must now learn that order can be taken too far, and that his rules (such as his prohibition against killing) cannot be absolute, as is the case here where he finds himself up against a force willing to destroy a corrupt city. Batman goes the opposite route: he decides Gotham's life is more important than that of Ghul's (who he tacitly dooms). By confronting Ghul's fanatical concept of order, Wayne is forced to understand not only his own principles but the extreme occasions on which he must break them.
Joker = Chaos
While it would be easy for Batman to just kill off his archnemesis, the Joker, the character cannot bring himself to do so. On a very deep level, Batman still believes in justice and order. According to the Joker, however, this is only Batman's delusion. In reality, our hero is only human, and, when revealed, the citizens of Gotham will attack the flawed man behind the mask.
Conversely, if he kills the Joker, Wayne will be doing what the villain wants him to do, proving that he is no better than those he fights against. The Joker's campaign of terror on Gotham is a series of moral tests, and interestingly, "Batman loses most of these confrontations. The Joker is able to figure out his flaws and use them against him."
In the end, chaos is only defeated because Batman is forced to sacrifice Rachel, one of the most important figures in his life. As Jack says, "the chaos of the world doesn't care about any rules, and in order to be successfu,l he needs to fight chaos." His ideals are put to the test, time and time again.
At the end of the trilogy, order has been restored not only to Gotham, but to Bruce's own life.
Harvey Dent = Hatred
Harvey Dent's hatred is a product of Batman's actions, the selfishness that caused Rachel's death and made him see the world as an unjust place. When Batman ultimately kills Harvey, the people of Gotham turn their hatred against him, coming to understand that what he does is not for himself at all, but only for the city, and that his vocation is one of sacrifice.
Bane = Pain
Bane wants to destroy everything Batman stands for, and the only way to do this is to force Batman out; only then will Bane be able to destroy Gotham, forcing Batman to watch it burn. While the villain's physical strength is able to break Batman's body, Bane cannot defeat his spirit (ironically, during one of their first fight scenes, Bane verbalizes just this sentiment). Batman triumphs because he maintains his spirit while enduring the physical pain, whereas Bane's physical resources are stronger than his internal ones.
Every filmmaker would be wise to consider the internal conflicts that drive every successful tale.
At the end of the trilogy, order has been restored not only to Gotham, but to Bruce's own life. It's hinted that he will be able to lead a life outside of Gotham, and, in doing so, will leave Batman behind. The city will be left in good hands. Just like in a classical drama, the curse has been lifted, and, though the cost paid has been great, order has been restored. The neat thing about Jack's video is that it makes you think about big-budget popcorn movies as not just entertainment, but vehicles that communicate story. They use archetypes of meaning that have informed narratives for thousands of years in order to instill key messages about the human condition.
The skillful way Nolan's films deploy these devices are a key reason for their standing out from other big-budget superhero films. Every filmmaker would be wise to consider the internal conflicts that drive every successful tale, and to reflect on how to embody them within their own stories. In doing so, they become more than the sum of their parts (or the sum of their supervillains, or Batmobiles, or whatever the case may be).