A new interview reveals that the most iconic line from Christopher Nolan's *The Dark Knight* — Harvey Dent's "You either die a hero, or live long enough to see yourself become the villain" — was not written by Nolan himself but by his brother and frequent co-writer, Jonathan Nolan. Speaking with Cillian Murphy, Nolan admitted the line still "plagues" him precisely because it is the one that resonates most with audiences, yet he cannot claim credit for it, adding that it "kills" him. This matters because Nolan writes all his own films but is often criticised for clunky dialogue, making this widely quoted exception notably significant to his legacy.

Jonathan Nolan has long worked alongside his brother, contributing the source story for *Memento* and co-writing *The Prestige*, both *Dark Knight* films and *Interstellar*, with Christopher's wife, Emma Thomas, producing throughout. Since their last collaboration, Jonathan has built an independent career, creating *Person of Interest* and *Westworld* for television and producing/directing Amazon's *Fallout*. Nolan reflected that the line's power lies in its universal theme of society building people up only to tear them down, which he said applies both to Batman and to Dent's downfall as Gotham's district attorney.