Good casting can mean the difference between whether a movie is going to succeed or fail. After all, a lot of great films have been carried by the strength of their performances more than anything else. But when you are choosing actors for movies that are adapted from popular source material, there is additional pressure coming from a dedicated and established fan base with very strong opinions about how they think their favorite characters should be represented.

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For a long time, superhero and comic book enthusiasts have been especially vocal about the casting choices made by studios and filmmakers when bringing iconic heroes and villains to life on the big screen. And many of them have not been kind. In a few cases, some legitimate points were probably raised. But mostly, it just seemed like people whining and arguing over petty reasons. And, of course, there were the instances where, whatever anyone's concerns might have been, actors were cast, reviled, and then blew everyone away with how well they played the part.

Hugh Jackman As Wolverine

Hugh Jackman as Wolverine

Yes, believe it or not, there was a time when nobody could imagine Hugh Jackman in the role of popular X-Men member Wolverine / Logan. In the comics, Wolverine was a gruff Clint Eastwood loner type with a quite literally monstrous temper. And he was short. That was something a lot of fans were stuck on: Wolverine was a stumpy runt of a man. So, when Hugh Jackman, a 6-foot tall Australian unknown at the time whose previous work was song-and-dance theater, was chosen to play the character in X-Men (2000), eyebrows were raised.

And yet, Jackman embodied Wolverine's essence to such a degree that fans quickly forgot about their physical dissimilarities. Now, it seems sacrilegious to think anybody else could be a better fit for the clawed mutant anti-hero than Jackman.

Tobey Maguire As Spider-Man

Tobey Maguire as Spider-Man

Spider-Man was Marvel's flagship character, and the inevitable film adaptation went through quite a tumultuous development before it finally got made. Still, there were some doubts around the main star, Tobey Maguire. Before Spider-Man (2002), Maguire was known for dramas like The Cider House Rules (1999), which was hardly a bad resume, but nothing that screamed superhero potential. He certainly did not look like one, either.

But not only did he bulk up for the role, Maguire endeared himself to audiences by effectively capturing the awkward "everyman" persona of Spider-Man's alter ego Peter Parker. Since then, multiple actors have filled his shoes in subsequent reboots and spin-offs who arguably surpassed him in representing other aspects of the web-slinger's character, but Maguire forever remains a favorite among Spider-Man devotees.

Robert Downey Jr. As Iron Man

Robert Downey Jr. and Iron Man in the comics

It definitely seems ridiculous today, but back before Iron Man (2008) and the Marvel Cinematic Universe (MCU), casting Robert Downey Jr. in a lead role (or any major part really) was considered an understandably risky move. It was not that he lacked the talent, far from it. Downey's past personal issues and volatile reputation just made people (particularly studio executives) nervous, even if he was genuinely setting his life straight.

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Then the movie was released, a game-changing franchise was birthed, and a legend was cemented. Downey actually elevated the source material by injecting Tony Stark, a.k.a Iron Man, with a likably narcissistic charisma that made Downey synonymous with and reignited interest in a character that was not as prominent as other Marvel properties.

Heath Ledger As The Joker

Heath Ledger and Joker in the comics

The Dark Knight (2008), the sequel to Batman Begins (2005), Christopher Nolan's mature and grounded re-imagining of Batman in film, was hotly anticipated for, maybe above all else, reintroducing Batman's archenemy, the Joker, to the cinematic landscape. However, confidence was shaken by the reveal of Heath Ledger playing the character. How could a guy recognized for being a pretty boy romantic lead believably portray Gotham's Clown Prince of Crime?

Well, once the movie started rolling and Ledger's performance made itself known, he completely disappeared behind, not just the make-up, but the voice, tics, and chilling yet mesmerizing unpredictability that Ledger had skillfully crafted for his interpretation of the Joker. It was a masterclass of acting that secured a lasting legacy for an artist who was taken too soon.

Anne Hathaway As Catwoman

Anne Hathaway and Catwoman in the comics

Here was an example of fresh ideas being weighed down by what came before them. Michelle Pfeiffer's sultry and deranged depiction of Batman's on-and-off romantic interest Catwoman / Selina Kyle in Tim Burton's Batman Returns (1992) has long been held up as the definitive version of the character outside the comics. When it came time to revamp her for The Dark Knight Rises (2012) and Anne Hathaway was cast, people were predictably dissatisfied.

Sure, Hathaway had already demonstrated strong capabilities as an actress, but she was still primarily associated with her "wholesome girl" image from movies like The Princess Diaries (2001), in addition to unending comparisons with Pfeiffer. Hathaway clearly did not let that stop her though, and she made the role her own, evoking a cunning and cool-headed femme fatale more consistent with the world that Christopher Nolan had designed.

Gal Gadot As Wonder Woman

Gal Gadot and Wonder Woman in the comics

A live-action theatrical Wonder Woman movie was something that fans wanted for a while. When Warner Bros. and Patty Jenkins eventually got around to making one, the original shortlist for the eponymous heroine consisted of some unexpected names before it was settled that Israeli model-turned-actress Gal Gadot would be her, a decision made by Zack Snyder. The criticism that followed focused on Gadot having too small and slender a physique to be credible as the Amazonian warrior Wonder Woman / Diana Prince. In all fairness, it was a reasonable point that was just not delivered reasonably.

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But whatever she outwardly lacked in brawn, pre- or post-training for the role, Gadot more than made up for with the amount of humanity that she infused into Wonder Woman (2017) with her performance. The film was Gadot's first as a full-on lead, and some growing pains may have been noticeable, yet she exceeded expectations and has since only proven herself further to be an ideal Wonder Woman.

Tilda Swinton As The Ancient One

Tilda Swinton and the Ancient One in the comics

This was a fascinating and extremely tricky situation. The Ancient One, as known in the pages of Marvel Comics, was a Tibetan sorcerer who trained Doctor Strange, Marvel's famous mystical superhero. During work on a movie about Strange, the filmmakers wanted to avoid a perceived stereotype with his mentor, yet in doing so, they also risked upsetting those who might feel that the film was being robbed of an Asian presence. In the end, significant creative changes were made, the Ancient One was gender-swapped, and veteran British actress Tilda Swinton was cast. Needless to say, this compromise pleased few.

It was a catch-22 that everyone had to just make the best of. Swinton certainly did. As the Ancient One in Doctor Strange (2016), she created an enigmatic and complex individual with apparent wisdom that belied her relatively youthful appearance and mischievous behavior, one who would continue to pop up in the Marvel Cinematic Universe/Multiverse beyond her introductory installment.

Michael Keaton, Ben Affleck, And Robert Pattinson As Batman

Michael Keaton, Ben Affleck, and Robert Pattinson with the comic book Batman

When are people going to learn? There has never been a bad cinematic Batman / Bruce Wayne, except George Clooney, but even then, it is debatable how much of that was miscasting or simply a (delightfully) terrible movie that sucked all the desire to put in effort from Clooney. Of all the Batman actors, Michael Keaton, Ben Affleck, and Robert Pattinson have received the most (if any) backlash.

Keaton was known as a comedic actor. Affleck already crashed and burned with another beloved superhero. And Pattinson had the ghosts of the Twilight franchise hanging over his head. But they all succeeded in realizing their own versions of the Caped Crusader. Keaton became a trailblazer with his portrayal of an eccentric and misunderstood recluse hiding a subtle dark nature. Affleck brought seasoned experience to a grizzled and world-weary vigilante. And Pattinson channeled a tranquil fury primed for explosion into a younger Dark Knight still figuring himself out.

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