Main X-Men Film Series guesses here.
In the movieverse, Emma Frost is Cyclops' motherShe'd be way too old to be his girlfriend and it kind of fits with the decision to make Havok his father instead of his younger brother. On top of that, it would be kind of amusing to see everyone's favorite snarky, white lingerie-clad Dominatrix become the mother of the guy that she's currently sleeping with. Because, y'know...if you're going to annoy fans by messing with Canon, you might as well have some fun with it.
- Jossed. Havok is still Cyclops' brother.
Xavier was always bald.That's why he told Beast not to touch his hair because he was really wearing a wig. Maybe he uses his powers to make people think that he has hair.
Darwin is alive.He's Darwin, he can survive being atomized by a condensed plasma blast! He just needs some time to put himself back together. The comics support this idea; he did survive having his body destroyed. He grew a new one.
- Perhaps he turned into energy and was absorbed into Alex? He's alive but in a state nobody can realise it.
Fill in the continuity holes here.The movie has too many similarities to the other films to be a reboot, so what happened was...
- Charles regained his ability to walk before his appearance in Wolverine and The Last Stand's prologue, but lost it again before the original movie.
- Erik occasionally found himself on good enough terms with Charles to work with him, such as when they build the second Cerebro.
- Hank's cameo in X2 was either old footage, an actor hired by the real Hank to make public appearances, or the result of a temporary cure.
- Confirmed to be that third one. Though originally for X2, Hank was supposed to be shown turning into Beast when the "destroy all Mutants" plan was launched toward the end, showing that his human-looking self was some sort of disguise.
- The Emma Frost that appeared in Wolverine was a separate character from the Frost in this movie, perhaps her daughter.
- The young "Storm" and "Cyclops" in this movie were actually just similar-looking mutants.
- The reason Xavier was surprised by Erik's helmet in the first movie is because the original helmet had been lost for years at that point.
- The incorrect ages given by Charles in the first movie are the result of psychic tampering with his memories (perhaps by this movie's Frost, or even by himself).
- Emma Frost erases Charles' memory of the helmet, and possibly his memories of Mystique. She could have also erased Mystique's memories of living with Charles.
- Or Mystique was just so messed up after killing Bolivar Trask (in the original "Days of Future Past" timeline, before Wolverine changed the past) that by the time of the original trilogy 30 years later she truly was a cruel, "cold-hearted bitch" who wouldn't give a second thought to sabotaging Cerebro and harming (potentially killing) Charles. After so much time spent with Magneto, doing who knows what, any sibling bond she had with Charles was totally forgotten. And Charles was so hurt by her betrayal that he simply never mentioned that he grew up with her.
- The Dr. Shaw who was debating with Hank in X2 is Shinobi Shaw, Sebastian's son in the comics. His full name could be Sebastian Shaw Jr., since his first name was revealed to be Sebastian in the novelization.
Let's pretend some legal troubles have vanished for a second.Let's pretend Marvel Studios still owned the film rights to X-Men and that this movie was in continuity with the MCU. In that case, the helmet that was given to Shaw by the Russians was not built or designed by them but instead found in an archeological dig. To be more specific the helmet was found in a ditch with a bunch of very large human shaped packs of ice and a single seemingly human skeleton that was wearing some shiny armor and holding a sword with the word "Baldur" written on it in norse runes. The helmet was merely given to Shaw because thems russkies knew he liked fancy stuff and he discovered its ability to block telepathy on accident later and lied about its origins because it reminded him of his old rival Johan Schmidt. Other fun ways we could tie first class into the MCU? List below if you want.
- Mystique's slowed aging could be used as the basis to introduce the infinity formula. Which then fell into Shields hands after Magneto broke into the CIA. Possibly using some on himself meaning they wouldn't have to recast Michael Fassbender for modern stories.
Magneto lived in Ireland for a few years.Hence his having a noticable touch of an Irish accent - he learned to speak English in Ireland. It's also posible he was hunting Otto Skorzeny who was living in Ireland at the time.
X-Men movieverse is an Alternate History in which JFK wasn't killed.There are rumors that the X-Men: Days of Future Past movie will begin with Magneto killing JFK, explaining the bullet's weird trajectory. In the comics, Bad Future was the result of Senator Kelly being assassinated by the Brotherhood, but movie Kelly is too young to be important in the timeframe of the movie. So I think it will be like this: Magneto assassinates JFK, causing the Bad Future, which will have the actors from the original trilogy reprise different versions of their characters. In the end, JFK's death will be prevented using Time Travel, thus causing the X-Men movieverse as we know it.
- Or, for a version with less Alternate History, the X-Men will still fail to save JFK, but will manage to cover-up Magneto's involvement, thus preventing the anti-mutant hysteria that caused the Bad Future.
- Jossed; In X-Men: Days of Future Past JFK is dead and the government believes Magneto killed him, but Magneto insists he was actually trying to save the president and someone stopped him. And the Bad Future is caused by Mystique killing Trask, not this.
The Man In Black is Fred Duncan.In some of the earlier X-Men issues, FBI agent Fred Duncan served as the team's government liasion. The Man In Black isn't an FBI agent, but he serves a similar role in the movie. In the sequels, he could serve as the team's spy in the CIA.
Shaw wasn't actually killed.The coin Magneto shoved through his head seems to have missed his medulla oblongata, the part responsible for life functions. Shaw was left alive, but seriously wounded (maybe for life), dependent mostly on the common humans he scorned.
Klaus Schmidt is related to Red SkullThe Red Skull from Captain America: The First Avenger to be specific. His name is Johan Schmidt and they share an interest in higher life forms than humans. They could be family, in-laws, or maybe part of a Evilutionary club whose members adopt the name "Schmidt". It's such a common name that it could be an ironic in-joke for the superpowered elitists. That was probably the idea behind his name. Fox wanted to use as much of Red Skull as possible without being sued.
- Perhaps a scene that died on the cutting room floor went along the lines of:Nazi: You are Herr Schmidt?
Shaw: I am afraid the Red Skull is indisposed. He sent me in his stead. I am Sebastian Shaw.
The first X-Men team was the inspiration for the Avengers InitiativeAgain, assuming a hypothetical universe where the legal problems separating Fox and Marvel studios do not exist. In fact, given the 60s spy fiction setting, and factoring in the original inspiration for comics Hellfire Club, perhaps the team in this movie is just an alternate universe version of a very different group of Avengers.