Summary

• Fox's X-Men movies set up Mister Sinister's live-action debut but he never officially appeared.
• Mister Sinister was teased in X-Men: Apocalypse, Logan, Deadpool 2, and New Mutants.
• Future plans included Jon Hamm potentially playing Mister Sinister, who would have finally appeared in Fox's canceled X-Men: Fear the Beast movie.

Although there were plenty of set-ups and teases for the live-action debut of Mister Sinister in Fox's X-Men movies, the classic villain never made an official appearance. Following the events of 2014's Days of Future Past and the creation of a new timeline with an all-new cast, subsequent X-Men movies began introducing new characters and, most notably, new villains. As a result, this included quite a bit of foundation laid for the arrival of Nathaniel Essex aka Mister Sinister.

Having recently made his on-screen return in Marvel Studios' animated X-Men '97 series, Mister Sinister has reminded audiences how great he would be in live-action as a true embodiment of Machiavellian evil, working behind the scenes and scheming to achieve a genetically perfect race of mutants. That said, such an opportunity would now likely happen in the MCU, disregarding all the established references and set-up featured in the previous films. To that end, here's every way Fox's X-Men movies set up Mister Sinister, and why he ultimately never appeared on the big screen.

6 X-Men: Apocalypse's Post-Credits Scene

Essex Corp And Weapon X

Although Hugh Jackman's Wolverine created a new timeline in Days of Future Past, his past self still ended up in the custody of Col. William Stryker and the Weapon X program by the movie's end. As a result, 2016's X-Men: Apocalypse saw Stryker attempting to capture Xavier School mutants, only to be rescued by younger versions of Cyclops, Jean Gray, and Nightcrawler after they found and unleashed Wolverine. Going into a berserker rage, Logan was freed and set loose to presumably the X-Men years later.

That said, X-Men: Apocalypse features a major post-credit scene teasing Mister Sinister. Returning to Weapon X, a group of men arrive to collect samples of Wolverine's blood, placing his blood and DNA in a briefcase identifying these men as of the Essex Corporation, connecting to Mister Sinister's Nathanial Essex and his work experimenting on mutants, the X-gene, and cloning. Likewise, this post-credits scene carries direct ties to the events of 2017's Logan set decades into the future.

5 2017's Logan Featured Connections To Essex Corp.

Wolverine's DNA And Cloning

In Logan, it's revealed that Wolverine's blood came to be in the possession of Alkali-Transgien, a subsidiary of Mister Sinister's Essex Corp, and the continuation of Weapon X (which had been located at Alkali Lake). Using Logan's blood, a clone of Wolverine was created known as X-23 aka Laura Kinney. Sharing his mutant abilities and even her own metal claws, Charles Xavier confirmed that Laura was effectively Logan's daughter in this darker future where Alkali-Transgien was responsible for suppressing the emergence of the X-gene and turning mutant children into their very own living weapons.

Under the supervision of Doctor Zander Rice, Transgien also created X-24. Another Wolverine clone created in the wake of several of their child subjects' escape (including Laura), this new X-24 clone was a fully adult male who was believed to be easier to control. While this proved not to be the case with X-24 becoming far too feral to be fully tamed, X-24 and Logan did end up killing each other. Regardless, the massive genetic manipulation and cloning on display is certainly on par with Sinister's typical modus operandi (even if he didn't make an appearance himself).

4 Essex House Featured In Deadpool 2

Housing "Wayward" Mutants

2018's Deadpool 2 continued to tease Mister Sinister with the Essex House for Mutant Rehabilitation. Following the death of his fiancée Vanessa at the beginning of Deadpool 2, the X-Men's Colossus tries to give Wade Wilson a new purpose in life by offering him the chance to become an X-Man himself. This leads to Deadpool's first mission to calm down a young pyrotechnic mutant named Russell. Refusing to live at the Essex Home any longer, Wade was the first to realize that Russell was being abused and more than likely experimented on as well.

The mistreatment extended far beyond Russell alone. After all, Domino revealed she'd escaped the Essex House herself as a child following her own traumatic experiences with the staff and their attempts to brainwash the children via religious indoctrination. It's also worth noting that Russell becomes a target by the time-traveling mutant Cable who comes from the future to kill Russell before he can become a killer due to the Essex Home's abuse. Considering Cable's own origins which are directly tied to Mister Sinister, it's yet another interesting point of connection that could have helped set up Mister Sinister in a future X-Men film.

3 New Mutants Teased Mister Sinister

Milbury Hospital and Mutant Experiments

In 2020's New Mutants, a group of young mutant teens find themselves trapped together in a largely empty hospital, being supervised by one Doctor Cecilia Reyes. Working for the Essex Corporation, Reyes' secret goal was to train the teens to become mutant assassins and living weapons before sending them to Alkali-Transgien. Not only does she wear a red and black pin resembling Mister Sinister's signature red diamond on his forehead and the logo of his company, but the hospital itself is also a major tease for the classic X-Men villain as well.

Referred to as the Milbury Hospital, New Mutants' primary location is a reference to Milbury House, the ancestral home of the Essex Family. Likewise, "Milbury" was a frequent alias used by Sinister during his centuries of life. As such, it seemed as though Milbury Hospital served as the initial staging ground before Reyes would send the best candidates to Alkali-Transgien to become living weapons. Likewise, any who couldn't be controlled were simply executed after their DNA was taken for future experimentation. Again, Mister Sinister's presence is felt and his dark work is shown without the villain himself ever appearing.

2 Jon Hamm Was In Talks Play Mister Sinister

Future Plans Were In The Works

Amid these final X-Men movies, rumors persisted regarding which actor might be tapped to play Nathaniel Essex and bring the pure evil of Mister Sinister to life, finally providing the X-Men franchise with an overarching villain on par with the MCU's Thanos. As such, big names like Brian Cranston were heavily rumored (and would have been quite exciting). However, it's since been revealed that Jon Hamm's talks with Fox about playing Sinister weren't just rumors and that he was considered for the villain role.

Overall, Jon Hamm could certainly bring a compelling version of Nathaniel Essex to life on the big screen. While Mister Sinister is incredibly dark with a complete absence of morals or ethics, more recent depictions have given him an air of charm and charisma that Hamm could pull off quite well. To that end, one would hope that Hamm would still be a contender for the role when and if Mister Sinister finally makes his live-action debut in the MCU in connection with the X-Men's imminent debut in Marvel Studios' cinematic universe.

1 Fox's Canceled Beast Movie Would Have Finally Revealed Mister Sinister

Sinister Would Have Been Set Up For A Future Crossover

While Fox's X-Men: Fear The Beast never happened, details about the script were revealed following its cancellation. Starring Nicolas Hoult as Hank McCoy aka Beast who's been playing the character in the new X-Men timeline, Fear the Beast would have seen McCoy facing off with Dr. Paul Cartier aka the Wendigo who attempts to turn Beast's transformation antidote into a weapon against mutants. However, Fear the Beast would have also featured the first on-screen debut of Mister Sinister near the movie's end.

Ultimately, it seems as though Nathaniel Essex's planned appearance in Fear the Beast would have likely set up a bigger role for Mister Sinister. Most likely, a bigger crossover would have been in the works to finally pay off all the various seeds and clues that had been established since X-Men: Apocalypse. However, 2020's New Mutants ended up being the final Fox X-Men movie that was produced.

Why Mister Sinister Never Appeared In Fox's X-Men Movies

Clearly, the vision for Mister Sinister in live-action was present. The foundations were being laid for an overarching villain who would have truly pushed the X-Men to their limits considering some of the stories he could have been involved with (like Jean Grey's clone Madelyne Pryor and the origins of Cable recently seen in X-Men '97). However, the true blame can be put on Disney's purchase of 20th Century Fox in 2019 and Marvel Studios' regaining the rights to the X-Men franchise, allowing for a fresh start in the near future.

The potential of the MCU is ultimately exciting for Mister Sinister's live-action debut and the X-Men at large. That said, it does mean that all of this set-up from the Fox movies likely won't be going anywhere. Regardless, it's fun to imagine where Mister Sinister's story could have gone in the Fox films as well as what it might look like going forward in the greater MCU.