Published October 5, 2023

X-Men: Mister Fantastic’s Missing Memory, Explained

Why did Professor X erase one of Mister Fantastic's memories, and what does that mean for the future of mutantkind? Find out here!

Mister Fantastic may be one of the smartest people in the Marvel Universe, but he doesn't know everything—and thanks to Professor X and Magneto, Reed Richards once forgot one of his most consequential discoveries. 

When Franklin Richards grew curious about his mutant heritage and started embracing Krakoa, Reed developed a device that could effectively hide the mutant gene so he could lock his son out of the mutant nation. When Charles Xavier realized what Mister Fantastic had created, he erased Reed's memory of the device, but left him with the memory of their unpleasant encounter.

During FALL OF X, times have changed for Krakoa, and the X-Men need Reed's missing memory to protect themselves from the anti-mutant organization Orchis and its worldwide campaign against mutantkind. Now, let's take a closer look at Mister Fantastic's missing memory and how Xavier stole it, as a new group of X-Men confront the Fantastic Four about it in X-MEN (2021) #27 by Gerry Duggan, Phil Noto, and VC's Clayton Cowles.


For most of his life, Franklin Richards was considered one of the strongest mutants in the world. While his parents—Mister Fantastic and the Invisible Woman—manifested their powers after exposure to cosmic rays, Franklin was born with his immense reality-warping powers and a slew of telepathic, telekinetic, and matter-manipulating abilities. 

With enough power to create universes, tame Galactus, and take on a Celestial, Franklin was considered an Omega-level mutant, one of the strongest mutants on Earth; he was even described as stronger than Omega level on a few occasions. In the wake of SECRET WARS (2015), Franklin used his powers extensively to help the Future Foundation remake the Multiverse by creating new realities. After several years of world-making, Franklin started burning out his powers and returned to Earth with his family.  

When Xavier, Magneto, and their allies brought the mutants of the world together to form the nation of Krakoa, they came to view Omega-level mutants as the nation's most valuable resource. Although most of the world's Omega-level mutants moved to or allied themselves with Krakoa, Franklin stayed with the Fantastic Four while his father tried to figure out what was happening with his fading powers. Nevertheless, Xavier and Magneto started making plans to bring Franklin to Krakoa in X-MEN/FANTASTIC FOUR (2020) #1 by Chip Zdarsky, Terry Dodson, Rachel Dodson, Dexter Vines, and Karl Story.   

When Franklin felt especially frustrated about his power depletion, Xavier, Magneto, and several X-Men approached the Fantastic Four about bringing him to Krakoa. While that encounter devolved into a fight over the merits of Krakoa, Franklin reconnected with his old friend Kate Pryde, who encouraged the young powerhouse to go where he wanted. After he chose Krakoa, Franklin tried to walk into one of the portals that allowed mutants to travel there instantaneously, but was unable to use it. Reed then revealed he had created the Code-X, a device that masked the mutant gene; he had used it on Franklin to stop him from accessing the gates. 

With the Code-X, Reed devised a way to isolate someone's mutant gene and superimpose a "ghost gene" over it. Once that process took effect throughout someone's entire body, they would no longer appear to be a mutant on a genetic level. 

The Terrigen Mist, the vapor that activates the powers of Inhumans, plays a crucial role in this process. While Terrigen Mist is lethal to mutants in large or moderate quantities, a small sample allows the Code-X to effectively hide mutant genes and make them seem like part of a normal human's DNA. Additionally, Reed theorized that the Code-X could potentially disable or replace an individual's mutant gene altogether. The masking effects of Reed's device lasted for roughly 10 days before it wore off.


After scuffling over Franklin, the X-Men and the Fantastic Four worked together to take down Doctor Doom and free several Latverian mutants who were under his control. Ultimately, Franklin began splitting his time between Krakoa and the Fantastic Four, while the resident geniuses of both groups tried to understand what was going on with his powers. Although the mutants and the Fantastic Four were seemingly back on good terms, Xavier and Magneto privately confronted Reed in X-MEN/FANTASTIC FOUR (2020) #4 by Chip Zdarsky, Terry Dodson, Rachel Dodson, and Ransom Getty. 

Xavier told Reed he had crossed a line by creating something that could remove a mutant's powers. Although Mister Fantastic said he would never use the Code-X for that purpose, Xavier telepathically erased Reed's memory and removed his ability to recreate the device. As Xavier told Reed, this was an act of mercy; he believed Reed did not understand the potential consequences of the Code-X and the existential threat it posed to mutants. However, Xavier allowed Reed to remember this encounter to underscore his seriousness. While Xavier confronted Reed, Magneto used his powers to grab the Code-X and smash it into pieces. 

In a cruel twist of fate, Franklin Richards learned he was never actually a mutant shortly after this. When a powerful alien called the Cormorant attacked, Franklin drained his powers holding off the villain. As Xavier explained, Franklin had subconsciously been using his powers to make himself appear to be a mutant on a genetic level, as revealed in FANTASTIC FOUR (2018) #25 by Dan Slott and R.B. Silva. Since Franklin was no longer a mutant, he lost his unlimited access to Krakoa.

Despite all of this, Mister Fantastic still accepted an invitation to the second Hellfire Gala, a state dinner and diplomatic event for the mutant nation. When Tony Stark bumped into Reed and made a joke about being mind-wiped by mutants, Reed quietly told Iron Man what Xavier did and what he forgot in X-MEN: HELLFIRE GALA (2022) #1 by Gerry Duggan, Russell DautermanKris AnkaC.F. Villa, and Matteo Lolli. After the pair agreed to continue discussing the issue later, Stark made a snide comment about Reed's mind-wipe to Emma Frost, who was shocked to learn it happened. Later that night, Emma told a similarly surprised Cyclops about Xavier's actions.


At the following Hellfire Gala, everything changed for the X-Men and the rest of Kraoka's mutants when the mutant-hating organization Orchis launched a devastating attack on Krakoa and the rest of mutantkind. Under Xavier's telepathic orders, most of the world's mutants were forced to walk through portals to parts unknown. The handful of X-Men who resisted his call went underground as Orchis launched a worldwide campaign against them. 

Similarly, the Fantastic Four became pariahs when Reed sent the Baxter Building and the people in its immediate vicinity—including Franklin—into a temporal pocket to save them from an alien attack. Although everyone was perfectly safe, they would not return to Earth for one year. After taking some time apart, the Fantastic Four reunited and moved to the Thing's family farm in Arizona. 

Under the direction of Emma Frost, the X-Men started making plans to recover Reed's lost memory of the Code-X device in X-MEN (2021) #27. Together, Synch, an older version of Laura Kinney called Talon, Ms. Marvel (Kamala Khan), and Rasputin IV, a time-traveler with the powers of five mutants, traveled to the Grimm family farm to speak to Reed. 

After Rasputin scuffled with the FF, Mister Fantastic said they all needed to trust each other and admitted he could have handled the situation with Franklin more tactfully. With Reed's permission, Rasputin used her telepathic powers and an old Cerebro unit to enter his mind. However, she could not restore what Xavier had taken away. 

As the disappointed heroes parted ways, Ms. Marvel mentioned that Xavier told her the Terrigenesis that activated her Inhuman powers had masked her mutant genes. With that, Mister Fantastic realized Terrigen was the key to his mutant-masking invention. As the X-Men left the Fantastic Four, Reed said he would reach out when he had a working X-Gene mask, which could be the key to keeping the X-Men and the world's remaining mutants safe from Orchis' clutches.

Witness the X-Men's reunion with the Fantastic Four in X-MEN #27, on sale now!

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