When it comes to the recently announced Avengers: Secret Wars movie, there are two comic book series the story could follow. The first, published in 1984, was followed by a new, even bigger iteration more than 30 years later.
To avoid any confusion, this article will refer to the 2015 version simply as Secret Wars while the original comics shall be referred to as Secret Wars (1984). The new Secret Wars takes place in a universe where Earth-616 and the Ultimate Universe Earth are on a collision course toward one another. These two Earths, which house alternate universe versions of superheroes and villains, are colliding due to an event called “The Incursion,” in which one of the two Earths must be destroyed in order to preserve both universes.
The issue that arises within the beginning of the Secret Wars comics is that too much time has passed since the two Earths appeared next to one another, and now destroying one of the Earths would simply destroy the other one as well, due to the proximity. Understanding the inevitability of destruction, Mister Fantastic (AKA Reed Richards) constructs a life raft of sorts to house what would become the next generation of humanity. Unfortunately, an accident causes Reed Richards to lose all the other members of The Fantastic Four.
The story takes a huge shift by immediately refocusing on what is now known to be Battleworld. Unlike in the 1984 comics, Battleworld here is revealed to have been created by Doctor Doom, with help from Doctor Strange and Molecule Man (though he isn’t mentioned to the public and is instead kept a secret). Doctor Doom rules this world and all of its people, which comprises many Marvel characters he had saved during his time as ruler of Battleworld, with the help of the Thor Corps. The Thor Corps is a group composed of alternate universe Thors, and they maintain order within the Battleworld. One other important detail is that Doctor Doom has altered the memories of Reed Richards' family to believe that he has always been their father and husband instead.
Battleworld itself is very hostile, with three main enemy factions existing beyond what is known as “The Shield Wall,” which separates Doctor Doom’s land of order from the rest of the planet. These factions are the zombies from the Marvel Zombie Universe. The second is the Annihilation Wave lead by Annihilus, and the third is the self-replicating Ultron robot army. So, while Doctor Doom has made a place for all that remains to live, he also has many threats present on the planet.
As it turns out, the Doctor Strange that resides as the sheriff of Battleworld is the same Doctor Strange from Earth-616, and when he finds the raft capsule, he opens it to find Peter Parker, Carol Danvers, Jane Foster’s Thor, Star Lord, Cyclops with the Phoenix Force, Black Panther, and Reed Richards. Also joining the heroes is Miles Morales from the Ultimate Universe, who hid as a stowaway on that universe’s raft. In the Ultimate Universe raft was that version’s Reed Richards (who served more as a villain in the Ultimate Universe), Thanos, and his Cabal (which is composed of Black Swan, Corvus Glaive, Maximus, Proxima Midnight, Namor and Terrax).
Doctor Strange explains to the heroes that Battleworld was made eight years ago by Doctor Doom, who created the world with remnants of the multiverse while also changing all the memories of the residents to believe that Battleworld has existed forever and that he was God. Doctor Strange also explains that Doctor Doom, himself, and Molecule Man took down the Beyonders and obtained their powers, which is how Battleworld was created.
The Ultimate Universe raft villains immediately begin to cause chaos as they kill the Thors sent to open their raft, and more Thors come to seek justice for the violence caused. The fighting continues to grow, and soon Doctor Strange is summoned to deal with the matter. He brings the heroes along, and Doctor Doom himself arrives upon seeing that Reed Richards is there. Cyclops attempts to attack Doctor Doom but is killed quickly. Upon seeing this, Doctor Strange sends everyone else to various parts of Battleworld, knowing that Doctor Doom would have killed them for not bowing down to him. In response, Doctor Doom kills Doctor Strange for his insubordination.
Afterwards, it is revealed that Molecule Man is still alive, and it is revealed that a version of him was made by the Beyonders for every reality that they created, as a form of self-destruct switch to destroy all universes when the time came. Eventually, the trio who took down the Beyonders used the other versions of Molecule Man to destroy the Beyonders completely, and they used Molecule Man as a conduit for all the power.
Unfortunately for Doctor Doom, the existence of the characters aboard the two rafts have begun to sew chaos in every part of the world they were placed in. Soon, all of Doctor Doom’s forces begin to turn on him. The Thor Corps are quickly swayed from Doom’s side by Jane Foster, and Carol Danvers persuades Mister Sinister to betray Doom as well. On top of that is a rebellion led by Maximus under the guise of “The Prophet” to overthrow Doom. The fight that breaks out allows for both versions of Reed Richards, Black Panther, Namor, and Star Lord to infiltrate Castle Doom. Also worth noting is that Namor and Black Panther have obtained two artifacts from Doctor Strange’s base: a device called the Siege Courageous that allows for the transportation of anyone to anywhere, and the Infinity Gauntlet with all the gems. These two items were left by Doctor Strange intentionally as an opportunity for someone to overthrow Doctor Doom should Strange himself be killed. With the plan in motion, the scene is set for the finale of the Secret Wars comics.
A lot of things happen in the last few parts of Secret Wars, including the death of The Thing, the revival of Groot with the World Tree, and the death of Thanos by Doctor Doom. Black Panther brings the zombie horde with him, controlling them with the Infinity Gauntlet and challenging Doom with Namor. Doom and Black Panther go on to fight while the two Reed Richards find Molecule Man.
Once the two Reeds find Molecule Man, the Ultimate Universe version betrays the Earth-616 Reed, although Molecule Man soon destroys the Ultimate Universe Reed and transforms him into food to sustain himself. After freeing the remaining Reed, he warns that Doctor Doom will soon be there, as he realizes that Black Panther was just a distraction. Doctor Doom and Reed Richards face off, but now Reed has been granted power from Molecule Man as well. The two fight and eventually agree that Reed would have done a better job with reshaping the universe than Doctor Doom did. Upon hearing their agreement, Molecule Man comes to the conclusion that he should prove it, and he sets himself off, unleashing all of his energy and essentially wiping the slate clean of everything.
The story comes to an end when Black Panther uses the time stone to go back to the point of the Incursion. What he finds is that the world is peaceful, so much so that there is no second Earth waiting to collide with them. Miles Morales gets sent back with Peter Parker, along with memories of the entire Secret Wars comic as a thank-you from Molecule Man for giving him a burger when the two met. As for the surviving Reed Richards, he is left behind with Susan Storm (Invisible Woman) and their kids to create the multiverse once again with Molecule Man and the Future Foundation. Molecule Man serves as the conduit of energy, Franklin creates the realities, and Reeds sends them out into the great unknown to form. The last pages of the comic shows a Doctor Doom in his castle, removing his mask and revealing that he has no scars on his face, which makes him laugh with joy.
One more important thing to note is that the end of this Secret Wars plot sets up the All-New, All-Different version of the Marvel Universe. As for Secret Wars being adapted into the Marvel Cinematic Universe, there is a chance that such a film would take more after this version than the original 1984 version. This is because it holds more of the heroes we’ve actually seen already, such as Carol Danvers as Captain Marvel, Star Lord, and Jane Foster as Thor (who is introduced in Thor: Love & Thunder).
Ultimately, though, there’s still a lot of missing material that would have to be introduced before Secret Wars got a true MCU film. That will likely come, at least in part, with a new Fantastic Four movie, which is set for a November 2024 release, and the events leading up to the Incursion. Also needed would be some form of introduction of Doctor Doom, as Secret Wars itself plays on the idea that you already know who Doctor Doom is and just how big of a force he is to be reckoned with. Since the MCU is primarily targeted not just at hardcore Marvel fans, but also the general public, more would have to be done so that people are aware of the main forces at play within this storyline regardless of if they've read the comics or not. That being said, it is exciting to think that this section of the Marvel Universe will be adapted to the big screen in the near future, and with each movie released we find ourselves closer to the reality that Secret Wars may indeed arise to be one of the biggest movies of all time.