Very rarely am I enticed to watch a movie more than once in a theater and "The Dark Knight" is certainly one of them. Christopher Nolan created a new genre of the batman movies with "Batman Begins"
And made people take the comic character with some level of seriousness.
Earlier batman movies were more like "Govinda" movies where you had to leave your brains at home to really enjoy the charade. What "Batman Begins" did was, it gave us a good insight into the character of Batman alias Bruce Wayne (that alias switch was intentional).
And what drove him to adopt a dual life style to protect a decaying city called "Gotham" (Can be equated to any metropolitan city with corruption). After watching the first movie I did buy the DVD and like many movie goers could not wait for the next one.