Much to the delight of fans everywhere, it looks like Michael Keaton may be reprising his role of Batman in the upcoming Flash solo movie. If true, this will be the first time Keaton has donned the cowl in nearly 30 years. First taking on the role in Tim Burton's 1989 film adaption of Batman (and again in 1992's Batman Returns), Keaton gave viewers a dark, brooding and tortured take on Bruce Wayne, a stark contrast to the last time viewers saw The Caped Crusader onscreen with Adam West's campy representation of the character.

So what inspired the tonal shift from West's cartoonish do-gooder to Keaton's sulking and contemplative Dark Knight? The answer lies in the comics. Much of the credit belongs to two comic book industry legends: writer Denny O'Neil and artist Neil Adams. The pair are often celebrated by comic book historians with returning Batman to his darker and more Gothic roots.

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And O'Neil and Adams are far from the only comic icons responsible for the grittier version of the character film-goers enjoy to this day. "I loved THE KILLING JOKE," Burton has said of Alan Moore and Brian Bolland's seminal and twisted Batman Story. "It's my favorite. It's the first comic I ever loved." During a lunch meeting in the late '80's, before making the movie, Moore reportedly advised that the most important aspect was that the director, "get Gotham City right."

It seems Moore's fellow creators were pleased with the results. Writing for ComicMix in 2014, the late O'Neil spoke of Burton's darker and more grounded take on the character, a take O'Neil had been instrumental in shaping:

"Maybe the idea of superheroes as a legitimate genre, equal to westerns and crime drama and the rest of the generic amusements, had been seeping into our collective psyche for years. But the genre wasn’t quite validated until…voila – it was! Tim Burton and his collaborators delivered what audiences didn’t realize they were waiting for..."

Stuff has to evolve and change or it dies,” the late O'Neil said in 2016 of his attempts to re-inject the dark into The Dark Knight. And the filmmakers seemed to trust O'Neil's advice on how the character should be portrayed, considering they asked him to pen the comic book adaptation of both Batman 1989 and Batman Returns three years later. Incidentally, O'Neil's adaptation of the first film received a deluxe hardcover re-release just a few months ago.

Neal Adams Batman

The darker take on Batman made popular by O'Neil, Moore, Adams, and others - which were eventually embraced by Burton - has stuck with the character's various film iterations ever since. Even The LEGO Batman Movie pokes fun at the title character's life of doom and gloom. So it should be interesting to see how Keaton plays the role if he does actually return in The Flash. What will life even look like for a senior citizen Batman? Will fans see him triumphantly returning to battle like The Dark Knight Returns? Or will he just be sitting back, using Batarangs to keep kids off his lawn? Only time will tell.

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