How did *The Dark Knight Returns* specifically impact Nolan's approach to Batman?

*The Dark Knight Returns* presented a significantly darker and more cynical take on the Batman character than previous interpretations. Nolan's portrayal of Batman in *The Dark Knight* trilogy mirrored this shift, emphasizing the character's weariness, his willingness to operate outside the law, and the brutal realities of Gotham City. The film's gritty realism, its exploration of moral ambiguity, and its depiction of Batman as a broken hero all owe a significant debt to Miller's graphic novel.