WARNING: The following article contains spoilers for Captain Marvel, in theaters now.

Speculation began from the moment Jude Law was cast in Captain Marvel that the Oscar nominee would play Mar-Vell -- that is, the Kree hero who originally went by the name Captain Marvel in the comics -- even when signs began to point to the classic foe Yon-Rogg. But Mar-Vell does appear in the Marvel Studios film; it just turns out fans were focusing on the wrong cast member.

Annette Bening recently surprised virtually everyone by confirming her long-mysterious role is that of the Supreme Intelligence, leader of the alien Kree and the embodiment of the collective knowledge of the greatest minds of the species. However, she wasn't telling the whole story. To communicate with Brie Larson's Carol Danvers, then the purported Kree warrior Vers with little knowledge of her own past, the Supreme Intelligence assumes the form of someone from her consciousness whom she can trust: her former mentor, Dr. Wendy Lawson. But there's another layer, as Lawson was merely a disguise for a Kree scientist named ... Mar-Vell.

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It's a surprise twist intended as an homage to Captain Marvel's comic book history. But it will no doubt further inflame those corners of fandom that, frankly, don't need another reason to be upset with the film. That's because, before they were aggrieved by the lack of smiling in the trailer, the choice of costume, the film's feminist themes or comments made by Larson about diversity (which, it turn, led to the review bombing of Rotten Tomatoes), many were displeased that it was Carol Danvers, and not Mar-Vell, receiving the cinematic treatment.

So, they get Mar-Vell, only as played by four-time Oscar nominee Annette Bening.

The Death of Mar-Vell

The circumstances under which Larson's Carol Danvers gained her powers remain a mystery for much of Captain Marvel, as her memory is all but gone, and only jostled when the shape-shifting Skrulls attempt to search through it themselves. Discovering that she was an U.S. Air Force pilot before she was purportedly killed while testing an experimental craft with her friend and mentor Dr. Lawson, Danvers finally regains her full memory of the fateful day.

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After their ship is shot down, Lawson reveals she's actually an alien scientist known as Mar-Vell. Desperate to keep the energy source of her intergalactic engine from the militaristic Kree, Mar-Vell attempts to destroy the core of the ship. But Lawson is shot and killed by Kree military commander Yon-Rogg before she can finish the job. Carol picks up the gun and shoots the engine, causing it to explode and bathe her in cosmic energies. The act grants her the powers that make her arguably the strongest person in the entire MCU.

NEXT PAGE: Marvel's Original Captain Marvel

Captain ... Mar-Vell

Introduced in 1967 by Stan Lee and Gene Colan in Marvel Super-Heroes #12, Mar-Vell was a Kree spy who adopted the identity of Walter Lawson and initially hid himself among humanity. Eventually coming to see the people of Earth as worthy of protection, he became the first Marvel Comics hero to use the name Captain Marvel. Mar-Vell was responsible for empowering Carol Danvers, but it was because she was near the explosion of a Kree device rather than trying to destroy it herself.

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Eventually becoming an Avenger and turning his back on the Kree, Mar-Vell was one of the Earth's most dedicated defenders. However, his time ended in 1992 with The Death of Captain Marvel graphic novel by Jim Starlin. After discovering his exposure to a nerve gas had left him with cancer, Mar-Vell makes his peace with death and passes away. While Mar-Vell has been briefly restored to life during events like Chaos War and Avengers vs. X-Men, or fakeouts like Civil War and Secret Invasion, the character has never fully been resurrected, a rarity in superhero comics.

That's Dr. Lawson To You

Recasting Mar-Vell as a woman fits better within the tone and story of Captain Marvel, removing any obvious romantic connotations between the characters. That allows Carol to stand on her own as a hero instead of being inspired by another. It also recasts Mar-Vell in light of previous takes on the character. While the comics' Mar-Vell was always more of a hero, this take is able to focus on the scientific aspects.

Bening is also a fantastic pick for the part, as she portrays the natural heroism of Mar-Vell while fostering a mentor relationship with Carol. It also makes sense to tweak Mar-Vell. The character has been more or less dead since 1982; for the better part of four decades, he's been more of a footnote in the history of other people than an actual presence in the Marvel Universe. There was plenty of room to make something new with the character, and what he, or she, means to Carol Danvers. Just look at how the Supreme Intelligence assumes the appearance of Mar-Vell while speaking to Carol. It wants to inspire respect and loyalty.

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But some fans have still clamored for the return of the classic Mar-Vell, rather than Carol Danvers, in Captain Marvel. Instead, the film has it both ways, with Mar-Vell still playing a role in the origin of Carol Danvers.

Directed by Anna Boden and Ryan Fleck, Captain Marvel stars Brie Larson as Carol Danvers, Samuel L. Jackson as Nick Fury, Jude Law as the commander of Starforce, Clark Gregg as Phil Coulson, Lee Pace as Ronan the Accuser, Djimon Hounsou as Korath the Pursuer, Gemma Chan as Minn-Erva, Ben Mendelsohn as Talos, Lashana Lynch as Maria Rambeau, Algenis Perez Soto as Att-Lass, McKenna Grace as a young Carol Danvers and Annette Bening as Mar-Vell/the Supreme Intelligence.