The Joker is the most iconic villain in comic book history. He is Batman's nemesis, but in a way, he is also Batman's other half. One can't exist without the other. One of the reasons this is true is because Joker represents all that Batman fears: that he is no better than the criminals on whom he wages war. It would not take much to push Bruce Wayne into madness. He could easily become what he hates most — especially when his sanity has been challenged by someone as depraved as The Joker.

Throughout the history of the Batman franchise, many actors have played Joker to much critical acclaim, from Jack Nicholson and Heath Ledger to, more recently, Joaquin Phoenix and, now, Barry Keoghan. While each made the characters their own, Christopher Nolan's The Dark Knight brought forth a grittier, more chaotic take on the character, with help, of course, from Ledger's talent and commitment to the role. What has cemented Ledger's Joker as one of Batman's best villains is due in part to the larger world Nolan created in The Dark Knight trilogy. Here's a look at how Nolan brought the iconic character to life in his version of Gotham and, ultimately, his vision of the beloved DC Caped Crusader.

Related: Why a Joker-Less Batman Movie Could Be a Good Thing

Casting The Joker

Heath Ledger Joker Dark Knight
Warner Bros.

Heath Ledger's Joker is a memorable character for anyone who has seen The Dark Knight. His performance as the clown prince of crime won him accolades, including a posthumous Oscar for Best Supporting Actor in 2009. However, Ledger was not Christopher Nolan's first choice for the role.

Nolan initially approached Robin Williams about playing Joker, but Williams turned it down. Next up on the list of actors who almost played Joker was Paul Bettany. The MCU actor was reportedly excited at being cast, but when no contract arrived, he found out that his agent had just been talking to himself; indeed, Nolan hadn't even spoken to Bettany's agent yet. Nolan then considered Philip Seymour Hoffman and Adrien Brody before finally settling on Ledger, who had impressed him with his performance in Brokeback Mountain. That's when things started to get interesting.

Nolan and Ledger's Collaboration Behind the Mask

the-dark-knight-heath-ledger-the-joker
Warner Bros.

Ledger’s Joker was the first to wear a mask. On top of that, he had several distinctive physical features that set him apart from his predecessors. In addition to his clown-like makeup and green hair, he also wore a white mask, similar to that of a mime, throughout different scenes in The Dark Knight. Although this mask was a key part of the character’s design, it was not originally included in the script for the movie. The idea came from Nolan while he was planning out other aspects of the film, citing early silent movies as inspiration for what iconography constituted fear. Though The Joker himself takes off the mask during the movie's opening heist, what it ultimately signifies is that Joker's clown make-up isn't really a disguise — his lack of identity is who he is, which is arguably more terrifying and, in fact, amplified by the fact that his only goal in the film is to create chaos for the sake of chaos.

Joker's Hair and Make-Up

The Dark Knight's Joker
Warner Bros. Pictures 

For the Joker, Nolan worked with hair designer Peter Robb-King to come up with the Joker’s memorable look. Nolan ultimately wanted to keep as much of Ledger's likeness as possible, a touch of realism that echoes across The Dark Knight trilogy. What's more, Ledger himself also offered suggestions for what his character should look like. In the end, the team decided that the Joker’s makeup should be applied in an asymmetrical pattern, with one side of his face done differently than the other. They also used certain colors to convey certain moods. For example, the team used more muted tones on the right side of Ledger’s face and brighter green tones on the left side of his face. The Joker is a character who doesn’t care much about keeping himself neat and clean, so his makeup is dirty and dented throughout the film. That decision was made to help convey the character’s disheveled nature as well as to show that he applies his makeup in a rushed manner.

How Joker Fit into the Larger Universe of The Dark Knight

the-dark-knight-heath-ledger-joker
Warner Bros.

When you think of Batman, the words "dark" and "mysterious" might come to mind. We love the caped crusader for his broody demeanor, his intense combat skills, and his ability to always seem a step ahead of whatever villain he's up against. But when Nolan took on the character of Batman in 2005 with Batman Begins, he decided to take things to a new level: he wanted to introduce the Joker at some point in his franchise as a foil to Bruce Wayne and Batman. On the one hand, Batman's code of ethics posed a problem against Joker's lack of code. Indeed, Joker's goal was to push Batman beyond his means in order to prove to him that he was just as bad as the criminals he stopped. This allowed for riveting tension through The Dark Knight, with Batman being back into morally-gray corners, desperate to find a way within his code to end Joker's crime spree.