The word retcon gets thrown around – sometimes wildly, sometimes recklessly – a lot in comic book circles to describe an act of rewriting a character’s history, changing seemingly fundamental details long thought to be that character’s truth. Spelled out, it’s “retro continuity,” or a sort of revisionist history that upends a status quo. For me it effectively boils down to one question: Does this irrevocably change the way we read the character’s previous appearances in comics?
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In the world of writer Jonathan Hickman’s X-Men, a good example is the revelations of House of X #2, in which the longtime human ally of the X-Men, Moira MacTaggert, is revealed to not only be a mutant, but a mutant with the power to reincarnate across lifelines with all memories of her previous lives in tact. While retcon has negative connotations – comics fans don’t have a sterling history with adapting to change – the Moira retcon is the centerpiece of the Krakoa era of X-Men. Call it a retcon, call it evolution, call it “I don’t care, this story rocks,” either way it’s the engine that drives this ship. And you can’t read Moira’s appearances in Uncanny X-Men now without that in mind.
Another possible character retcon in the works – one that fans have been questioning and debating since House of X / Powers of X – is Mister Sinister. Until recently, I hesitated really engaging with this question, but recent issues in the Dawn of X have increasingly added layers to the question whether or not Hickman’s working through a sizable Mister Sinister retcon as well.
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I’ll start from the earliest suspicions about the longtime X-Villain, and work forward through the Dawn of X to the most recent clues to determine what’s really happening with Mister Sinister here.

Glam Rock Sinister
In the first major appearance of Mister Sinister in Powers of X #4, our boy Nathaniel Essex takes the stage like a wrecking ball. He’s fabulous, motormouthed, and practically something out of an R-Rated Loony Tunes special. On this alone, plenty of readers were asserting that this wasn’t their Mister Sinister, the cold calculating genetics villain obsessed with Summers DNA but certainly not with epic capes.
This, though, is far from a retcon. Instead it’s really just the natural progression of how modern creators prefer to write the character, most notably coalesced in the Kieron Gillen written Uncanny X-Men. In “Everything is Sinister,” Gillen struck a goldmine for the character, endlessly cloned, running his own Sinister society, and yes, finally funny. Crucially, Gillen’s Sinister is gloriously ludicrous (he uses clone Sinister cows as bombs against Emma Frost) and still ultimately threatening (he guns for the power of Celestials and the Phoenix over the course of the run).
This is the template everyone since has followed to some degree or another, whether in shorter appearances like Spider-Man and the X-Men or Hickman’s own trial run in the 2015 Secret Wars event. If you’re less into this version of the character than the tired Summers and Grey obsessed geneticist of the 90’s, sure, but that doesn’t make it a retcon. On the surface it just means times have changed.
Sinister’s Past
The revelation that Professor X and Magneto are working with a mutant Mister Sinister is where we start getting into more interesting waters. Despite his presence as an X-Men villain since the late 80’s (cemented with his role in 1989’s Inferno), Mister Sinister was not actually known as a mutant until this moment.
On the surface, it’s hard to argue against this measuring up to retcon status. Not only is this version of Mister Sinister actually a mutant, but he’s been working – at least theoretically – at the behest of Charles Xavier and Magneto for years before the launch of Krakoa.
The initial meeting (from Powers of X #4) occurs during the nebulous timeframe of X^0 “The X-Men: Year One,” during a period where Magneto and Professor X were allied. It’s also (apparently) the first meeting between Sinister and these two, as Sinister wonders how they know about his work in genetics. In comics publication terms, this would most likely put the meeting between 1981’s Uncanny X-Men #150 (when Magneto first begins to really develop some potential allyship with the X-Men), and I’d argue 1986’s “Mutant Massacre” (while he doesn’t appear, Sinister is first named in this event, which he orchestrates).
Crucially, during this meeting the first Sinister in charge is not actually that interested in prioritizing the study of mutant DNA. He denies “mutantdom” as a cause of his. For his grandstanding, this Sinister clone is promptly shot in the head by the Sinister with the mutant gene (or at least, one of them). Xavier then mentally convinces him to prioritize mutant DNA collection, giving us the Summers / Grey obsessed Sinister we know throughout X-Men history, telling him he’ll forget this is because of Professor X and Magneto until the day the Prof wants him to remember.
The whole visit is a fairly neat trick because it allows a “secret history” while ostensibly maintaining Sinister as we’ve known him throughout X-Men comics history.
At the same time, “Sinister Secret #10” tells us – again, with whatever certainty we can put in Sinister’s gossip mag! – that we’re following a new Sinister in the Dawn of X; one that’s well aware of Professor X and Magneto’s previous attempts at brainwashing. As the secret reads:
“Which brainwashed mutant Sinister was replaced long before a certain bald somebody knew and has been in on the game for almost as long as the game was being played? Shhhhhh!”
So, we don’t know when the Sinister in on the game “took over,” but it’s entirely possible he’s been working out his own schemes as long as Sinister’s been in X-Men comics. This likelihood makes moments like Sinister’s experiments in the Kieron Gillen written Uncanny X-Men stand out so much more, when his experiments on mutant clones of Gambit, Summers, and Sabretooths, include a pit of the Phalanx!
Intriguingly, there is one extremely fun theory about Sinister’s Secrets – one I didn’t fit into my 20 theories for each secret Krakin’ Krakoa video – that takes this retcon to the next level.
The very first “Sinister Secret” states: “He’s trying to pretend that no one noticed he was wearing red shoes, but this truly sinister Sinister isn’t fooling anyone.” I had a bunch of theories on what this might mean, but it wasn’t until I heard a tidbit on Jay and Miles X-Plain the X-Men that anything really blew my mind.
On the podcast, Miles mentioned that right after Giant-Size X-Men #1, in the two part Uncanny X-Men #94 and #95, the All-New All-Different X-Men lose Thunderbird, who sacrifices himself on the mission. Due to a coloring error, shortly before Thunderbird’s death, there’s a brief panel where Thunderbird, John Proudstar, is suddenly wearing red shoes – in every other appearance, they’re blue.
This alone could easily fall into the ephemera of inside baseball comics facts, but for Sinister Secret #5 which states:
“Certain people are wondering where the tyrant-dispelling Sinister got his mutant gene. And while that really isn’t an interesting story, whom the DNA originally belonged to is. [John Proudstar/Thunderbird]”
Connecting the dots, what if that red shoed Proudstar was a Sinister clone (or Sinister himself), masquerading as John Proudstar? This would insert Sinister into the formation of the All-New All-Different X-Men, with access to the X-Mansion and all the potential secrets that might entail!
Here’s a version of how this could play out: Sinister captures John Proudstar, steals his DNA, then uses that to sneak his way into Xavier’s new X-team. He fakes his own death (or sends a clone with a kamikaze trigger) once he’s acquired the information he needs to secretly plot against Professor X, Moira, Magneto and company.
There are approximately a gajillion other possible integrations, but either way, Sinister’s involvement in this era of X-Men, puts his hands all over the formation of the most well known X-Men team of all time, much like his hands are all over the entire history of the Summers’ brothers.
Couple this with the X-Men Legacy revelation that Mister Sinister implanted a backup of himself into a young Charles Xavier to ensure his immortality, and I’m looking around Krakoa wondering who isn’t being directed by Nathaniel Essex on this island?
Lil Baby Essex
The most recent entry in the case for Sinister’s retcon came in the pages of Giant-Size X-Men: Fantomex, in a detail so seemingly besides the point, I didn’t even really begin to see what was in play until a number of eagle eyed Krakin’ Krakoa listeners called it out in the comments.
The Fantomex one-shot opens with a sequence of two scientists discussing their baby clone factory. One observes that among the randomly generated clones, there are two exact replicas (which is apparently unlikely to the point of near impossibility). The head tells him to keep one, and “throw away” the other, and one baby is given a circle on their forehead, and the other a diamond.
Now, as the issue plays out, every implication is that these two babies grow up to become Fantomex and Ultimaton (aka Weapon XV). But when you’re telling a story in the world of X-Men, and you choose to place a diamond on someone’s forehead, that raises Sinister questions!
A handful of Krakin’ Krakoa commenters have wondered if that could be baby Sinister. Personally, I find this quite unlikely for a few reasons. First, the remainder of the issue has absolutely nothing to do with Sinister, nor does he appear to have a likely role in the upcoming and final Giant-Size X-Men Storm. Second, we know Nathaniel Essex was born in England in the 1800’s, and while we aren’t given a date, there’s not much reason to believe this lab is set in that time period (although to be fair, until this issue we had no idea Fantomex had a history dating back as far as World War II).
That doesn’t mean I don’t think Sinister could be involved though. In fact, I think it’s actually very likely that one of the Doctors we see here is in fact a disguise of Mister Sinister’s.
That doesn’t mean I don’t think Sinister could be involved though. In fact, I think it’s actually very likely that one of the Doctors we see here is in fact a disguise of Mister Sinister’s. Not only does Mr Sinister have a history with the Weapon X program (see the early 2000’s Weapon X series for examples), but he’s basically a walking “was secretly involved in every part of your past” machine.
Just ask Cyclops, or again from X-Men Legacy, Professor X. Adding a secret degree of control to the rise of Fantomex and Ultimaton is a billion percent up Sinister’s alley, although certainly to what end is entirely up for unfounded theorizing.
This doesn’t really retcon anything I know about Sinister, but it adds yet another corner of the X-Men Universe under his thumb.
So Is He Retconned Or Not?
Strictly based on what we actually know to date, making this version of Sinister a mutant is close to a retcon! The problem is that since we don’t know when the Sinister aware of the Professor and Magneto’s grander plans really took over, it’s close to impossible to nail down any history of the character at odds with what Hickman’s presented since.
The potential change for me comes depending on what Mister Sinister knows and when. Again, Sinister is a virtual retcon engine by design, making him extremely difficult to truly change in ways that don’t reflect his creation. The character travels in secret origins, so what’s one more?
If the Red Shoes theory turns out to be true, though, all bets are off, and the history of Mister Sinister has the potential to be deeply changed. Not only might he have infiltrated the X-Men at their New Genesis, but who’s to say he didn’t hack into a secret conversation between Moira and Charles during his time at Xavier’s? If this Sinister is the one true Sinister aware of the brainwashing, then he’s integrated into the whole fabric of X-Men in ways we never could have guessed. And yes, I’d say that validates Moira’s fear of the schemer, and puts him firmly into an epic retcon I’m more than happy see play out.
I always liked Sinister since I was a kid, but I gotta say I like the Kieron/Hickman Sinister more. He has a bigger louder personality, he feels like he’s letting go of his one-note obsession with Summer’s gene pool & expanding his interests, his design with a slimmer body (when artists chose to draw him that way) & longer hair draws less comparisons with Colossus (Though Mikhail Resputin’s costume is still way too similar to Sinister’s), & when he’s being a fashion concious drama queen he’s funny AF.