Casting doesn’t always turn out the way anyone initially expects. In the case of Christopher Nolan's Dark Knight Trilogy, it took some twists and turns that ended up changing the face of pop culture. Heath Ledger -- whose indelible performance as the Joker in 2008’s The Dark Knight earned him a posthumous Oscar -- was apparently on Nolan's mind very early in the process. According to a report from NME in 2012, Nolan approached the actor about starring in 2005’s Batman Begins as Bruce Wayne. From there the casting took on a life of its own.

Changing casting ideas is nothing new. James Cameron famously had Arnold Schwarzenegger in mind for the hero's role in the original Terminator before wisely deciding to cast him as the titular killbot. Similarly, as recounted in the Batman Begins Blu-ray extras, actors like Cillian Murphy originally auditioned for the Wayne role, only to “switch sides” when Nolan decided he was a much better fit for Jonathan Crane. In the Ledger situation, however, it had much less to do with the filmmaker changing their mind and more to do with the actor.

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Batman posing on top of a building in Batman Begins

According to Nolan, Ledger was one of several whom he met when casting for the part of Bruce Wayne. His star was on the rise and he had earned a reputation as a serious actor in the likes of Monster's Ball. Nolan claims that Ledger shut him down immediately -- “quite gracious about it” according to NME -- but clearly having no interest in a superhero film.

Considering the state of the genre at the time, the actor had a reason for skepticism. While the Spider-Man and X-Men franchises were going strong, Batman had crashed and burned several years earlier with the disastrous Batman and Robin, while box office misfires like 2003's Daredevil didn't speak to a bright future. Even the hits were viewed as lightweight fare, and Ledger's ascent might have induced him to feel it was beneath him.

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That apparently changed upon release of Batman Begins, which not only revitalized the moribund DC movie franchise, but demonstrated that serious filmmakers could tell adult-minded stories with these characters. Nolan ended up casting Christian Bale as Wayne, who drew universal acclaim and became an A-list star on the strength of his performance. The inclusion of Michael Caine, Gary Oldman and Morgan Freeman in the cast spoke to the franchise’s ambitions, and its success helped give superhero films a boost just as the Spider-Man and X-Men series began to flag.

All of it made Ledger very interested. After watching the film, he actively lobbied to play the Joker in the sequel and Nolan cast him before the script was even written. According to the director, that gave Ledger months to prepare, and the actor “obsessed” about it as the story took shape. The results made movie history, and a tragic final act to a performer who departed too soon.

They also demonstrate how seemingly inevitable casting choices can turn on small things. Had Ledger shown an interest in playing Wayne, the resulting film and its legacy might have looked very different. As it stands, it’s impossible to view anyone but Ledger (and Bale) playing the parts they did in that iteration of the Batman story -- a choice that ultimately hinged on one man’s change of heart.

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