Hans Zimmer and Christopher Nolen worked together to produce the music for the dark night,
Hans Zimmer would create lots a fragments of short music clips and show them to Christopher.  Hans was taking the idea of anarchy to help inspire him. He was trying to create a a sound for the joker than was short and simplistic but also embodied the character of the joker. He needed it to have a sense o fear tension and chaos. He wanted to create something that was provocative and people could actually hate.

He used the idea of tension mounting and growing. But needed to keep it simple and make it work with the music so you could hear just a hint or a couple of second and you would know that the joker was involved.

The final score has used the simplistic idea well. It builds and builds without really changing which i think is quite effective because it will build up to the moment when you see the joker. It is quite but because of how unique it sounds it still has the same dramatic impact as a load music piece would