The Dark Knight trilogy was a very successful series of movies about Batman. Warner Bros. earned $2.4 billion at the worldwide box office from the three films. The actor who played Batman was Christian Bale and he earned about $54 million from the three movies. At the end of the third movie, he was offered the role again to continue with the fourth installment, but he declined. Even though he was offered $50 million—almost the same amount as he earned from the three movies put together.

The actor explained that from the beginning, the director Christopher Nolan envisioned a trilogy and thought that he should stop after the third movie. Christian Bale respected the director's wish and that's why the trilogy didn't become a quadrilogy.