Christopher Nolan defined a new approach to superhero movies.
If you watch superhero movies before and after The Dark Knight trilogy, you can see a distinct difference in the feel of them. They either go the Marvel route, of light hearted fun with a bit of a serious undertone, or the gritty, dark realistic approach to superhero movies that The Dark Knight trilogy created.
The Dark Knight trilogy wasn’t a superhero movie at all
It’s true, The Dark Knight should really be called a crime drama, instead of a superhero movie. When you take a look at the issues, conflicts and politics, it fits more into the crime drama genre rather than a superhero, go save the world kind of movie.
The Dark Knight Trilogy reintroduced compelling villains
Heath Ledger set the scale for what a good villain should be. He created the most iconic villain to date, and others, although they have tried to copy him, have never come close. Other villains often fall under the “simple evil” or the “overly complicated villain whose plan doesn’t really make sense” type that is confusing at worst and unoriginal at best.
The Dark Knight trilogy brought up serious issues
Not a lot of movies have played on the idea that superhero movies can deal with issues of tragedy, loss and discouragement. What other superhero trilogy kills off the main love interest in the middle of the second instalment? It creates a self-sacrificing character that has a lot more on the line than just saving random civilian #2 because of a loss in their past. No, batman truly loves Gotham, and will sacrifice everything, even the opportunity to be batman and perpetuating a lie, to preserve it.
The trilogy had a filmmaker with a vision
Nolan tries his best to use real-life practical effects because he cares. He casts A-list actors and criticized their performance until they get it right, because he cares. He takes years to develop a perfect story, because he cares. A superhero movie should be taken seriously, and the director should put in his best work for it.