WARNING: The following article contains major spoilers for Dark Phoenix, in theaters now.

Following the failure of X-Men: The Last Stand to satisfyingly adapt the "Dark Phoenix Saga," fans hoped to get a cosmic spectacle in Dark Phoenix, with Sophie Turner's Jean Grey taking a sinister turn after becoming possessed by a powerful entity. But while writer/director Simon Kinberg plays up the Phoenix's cosmic backstory, the film's finale was reshot with a more grounded approach.

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The filmmaker has said he felt that strategy would illicit more emotion and drama, as opposed to having explosions and debris flying though space in what we can only presume would have been all-out war. However, by taming the storyline, Kinberg didn't only drastically change the climax, he gave us a diluted version of the source material, which had the potential to be genuinely epic if done right.

THE PHOENIX'S LAST STAND ... AGAIN

Dark Phoenix was initially intended to conclude with Jean regaining her senses and using her Phoenix powers to fight off an alien armada in space. Throughout the film, Jessica Chastain's Vuk, a leader of the shape-shifting D'bari, coaxes Jean to destroy Earth and revive her alien race; rumors suggested her legion would have attacked the United Nations, leading Jean to return to the light and fight alongside the X-Men once more.

That would have led to Jean harness the full power of the Phoenix Force in space. However, instead, audiences are given an Earth-based brawl in which Kinberg (who co-wrote The Last Stand with Zak Penn) limits the climactic battle to a run-of-the-mill train sequence. There, Jean unites with her former teammates and Magneto's Brotherhood to fend off Vuk's shape-shifting soldiers. The sequence culminates in Jean taking Vulk into the sky, detonating and killing them both.

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That's a far cry from the space battle fans craved, which would have honored the source material where Jean was taken to the moon by the alien Shi'ar to answer for the Phoenix cosuming the D'bari's sun. Kinberg could have depicted something similar, with the X-Men coming to Jean's aid after Vuk's alien squadron attempted to hold her accountable for destroying their home world.

Having the D'bari attempt to ally with Jean, and Vuk try to extract the Phoenix Force from her, isn't a bad direction. However, when the time comes for Jean and Vuk to fight, it's pretty underwhelming. Most of the action comes down to Xavier and Magneto's charges brawling with the D'bari, leaving Jean to derail the train, and then take Vuk for a scalding death ride into the stratosphere.

We've seen train crashes in so many superhero movies before, especially in the X-Men franchise, so this ending doesn't feel like anything grand. Kinberg offers a cookie-cutter action blast that doesn't fit the scope of what the godlike Phoenix can do. In that sense, it's similar to when Famke Janssen's Jean took on the X-Men in 2006's The Last Stand, only for her to be killed by Hugh Jackman's Wolverine. Once again, rather than depicting the Phoenix as an avatar of cosmic destruction, we end up with an unhinged psychic, and Kinberg repeating the series' previous mistakes.

MARVEL GIRL ISN'T CAPTAIN MARVEL

Dark Phoenix Captain Marvel Social Header

Known in the comic books as Marvel Girl in her younger years, Jean Grey was unshackled by her bond with the Phoenix Force. Audiences received a taste of that in 2016's X-Men: Apocalypse when she incinerated En Sabah Nur. Many fans assumed that, with the Phoenix entity retconned to be of cosmic origin rather than a mental disorder as it was in The Last Stand, we would see Jean in a Dark Phoenix form similar to the comics.

Some of the cast did admit, however, they were routinely given rewritten scripts, so much so that Chastain wasn't sure whether her character was even from the comics. There were rumors the shape-shifting aliens in the film were originally meant to be the Skrulls, but with their prominent role in Captain Marvel, it's speculated Dark Phoenix hurriedly changed them to the lesser-known D'Bari.

"The finale had to change," admitted star James McAvoy. "There was a lot of overlap and parallels with another superhero movie that came out... a while ago." While Captain Marvel wasn't mentioned by name, Kinberg revealed the original finale would have drawn parallels between Jean Grey and Carol Danvers in her Binary mode -- something fans speculated about when they saw Brie Larson's Marvel Cinematic Universe hero cutting through the Kree armada.

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We can't assume Fox reshot Dark Phoenix based on knowledge of what Marvel Studios planned for Captain Marvel, as additional photography took place before the film's March release. However, Marvel's marketing teased enough that Kinberg & Co. might have been able to predict a climactic space battle.

That said, similar ideas aren't a big deal; the execution is what's important. To say Dark Phoenix couldn't have a woman in space destroying alien ships after Captain Marvel depicted the same thing timid and shortsighted. But, of course, to be honest, that pretty much sums up the approach to the X-Men movies. Nevertheless, by shackling Jean in the final act yet again, Kinberg takes away from the very essence of the character and ignores the improvements fans craved -- which would have also honored the source material and fixed what went wrong in The Last Stand.

Directed and written by Simon Kinberg, Dark Phoenix stars James McAvoy, Michael Fassbender, Jennifer Lawrence, Nicholas Hoult, Sophie Turner, Tye Sheridan, Alexandra Shipp, Kodi Smit-McPhee, Evan Peters and Jessica Chastain.