Sane: A Joker fanfic

He's terrorized Gotham for years. His laughter often means a city in ruins.
But when Batman finally serves him the justice everyone has craved, the tables quickly turn.
The revered and loved Batman is now a wanted man, and The Joker has won the hearts of millions.

But what happens when an unexpected figure from his past pushes him to commit the ultimate crime, alongside Batman?

Initially based on The White Knight comics.