Michael Fassbender & James McAvoy's X-Men Chemistry Came From Band Of Brothers
Brett Ratner's 2006 superhero film "X-Men: The Last Stand" is set in the near future, and features a climax wherein the powerful mutant Magneto (Ian McKellen) floats a portion of the Golden Gate Bridge through the air using only his magnetic powers. Dozens of characters appear, several of them lose their mutant powers thanks to an anti-mutation serum, and others die outright. So many dramatic things occurred, it seemed difficult to continue the film series in a cogent way; it didn't seem that the studio could still incorporate the X-Men heroes audiences had come to love.
20th Century Fox, as a solution, began producing a series of flashback prequel films about the X-Men characters in their respective youths. The fourth film in the X-Men series was called "X-Men Origins: Wolverine," and it told the story of how Logan (Hugh Jackman) came to have his metal skeleton and how he lost his memory, all prior to the events of Bryan Singer's first "X-Men" in 2000. The next idea was to be "X-Men Origins: Magneto," which was about the title character's harrowing experiences at Auschwitz. That ended up expanding into what would eventually become Matthew Vaughn's "X-Men: First Class," an X-Men film set in 1962 about the young mutant Professor Xavier (James McAvoy) and Magneto (Michael Fassbender) becoming close friends before splitting up over their differing ideologies. They replaced Patrick Stewart and McKellan respectively.
The key to making "First Class" work would be the relationship between McAvoy and Fassbender. Luckily, the two actors immediately had chemistry, as they had previously worked together on the 2001 HBO miniseries "Band of Brothers." McAvoy had a minor role, and Fassbender a supporting role, but the shared experience brought them closer together nonetheless.
They talked about it in a 2019 interview with Heavy Magazine.
Soldiers' camaraderie
"Band of Brothers" was a massive undertaking, featuring a cast of at least 23 actors in main roles, with dozens more supporting. Simon Pegg, Jimmy Fallon, Dominic Cooper, Tom Hardy, and Jamie Bamber also joined Fassbender and McAvoy in the ensemble. It seems that the miniseries, all about the camaraderie between soldiers, created a similar attachment between the members of its massive cast.
Just prior to the release of "Dark Phoenix," the tenth X-Men film, Fassbender pointed out that the two actors had indeed met during "Band of Brothers," some 20 years ago. McAvoy also shared that, "there was chemistry there from the beginning, and that is why we agreed to do this." McAvoy, it seems, was cast first, while Fassbender came in after to audition with him. Everything clicked immediately. Fassbender said: "James was at my audition when I first auditioned for Erik [Lehnsherr, a.k.a. Magneto] as well. James was kind enough to be there for me for that."
Their audition involved a lot of improv, and McAvoy and Fassbender immediately developed an actorly rapport, allowing them to merely have a conversation. The heady, extensive X-Men mythos wasn't important. What was important was that the two characters felt like friends. McAvoy said:
"All the scenes were so natural. [...] There were scenes when we were shooting that were almost two guys shooting the s*** about who they love, the people that they were in love with, and it did feel very comfortable. It just felt like a couple of guys and I think that was why it ended up working."
By the time the X-Men series had progressed to "Dark Phoenix," however, the two characters had a much more fraught relationship.
Dark Phoenix
In "First Class," Charles Xavier and Erik Lehnsherr were fast friends. In "X-Men: Days of Future Past," they were friends in the near future, but bitter enemies in the past (that film takes place in the 1970s and a futuristic 2023). In "X-Men: Apocalypse" (set in the 1980s), Magneto had his magnetic superpowers enhanced by a cult leader-like creature named Apocalypse and nearly destroyed a city. One can see how, by the time we get to "Dark Phoenix" (set in 1992), their relationship had soured. Only a few more years, and they will have caught up with the events of the original film.
When talking about the new Professor Xavier/Magneto relationship, McAvoy acknowledged the coldness between them, saying:
"I think they are on ice this time. [...] They've both pretty much gone separate ways and decided you do your thing and I will do my thing. They've annoyed each so much that they have decided not to talk full awhile — it's like 'I still love you but let's not talk for awhile, let's not see each other, and let's give each other some space. I'll be there but only call me if it is something important.'"
"Dark Phoenix" notoriously lost buckets of money at the box office, ending the franchise with a whimper, not a bang. It was followed by the much more modest "The New Mutants," a film without McAvoy and Fassbender, and also a notorious bomb (it was released during COVID-related lockdowns). A "Deadpool 3" is also in the works, and that film will take place within the auspices of the Marvel Cinematic Universe. Whether or not other X-Men characters will appear in that film remains to be seen.