Over the course of 23 movies, every major character in the Marvel Cinematic Universe has undergone some kind of transformation. There have been, quite literally, dozens and dozens of hero's journeys.
For some, the arcs have been super-sized versions of classic morality plays — Tony Stark (Robert Downey Jr.) became selfless, while the Guardians of the Galaxy learned the value of teamwork. Early on, Thor was on the same kind of path, assuming the throne of Asgard and appreciating its gravity and his responsibility. But by the time Avengers: Endgame gets rolling, the once-chiseled God of Thunder is a slob and drunkard, the comic relief (and punchline) in a movie with a universe-wide genocide as its stakes.
So what happened to cause such a wild swing in a network of individual movies that also work as cogwheels and sprockets in an intricately designed machine? Like everything else in the MCU, it required a lot of planning and collaboration, along with some creative risk-taking.
Marvel's massive movie output is overseen by Kevin Feige, who now has virtually full creative control of the company. But individual filmmakers are still able to leave their stamp on their own entries — Ant-Man and Black Panther are two very different movies, yet they peacefully coexist — and some filmmakers are even brought in to put their own spin on a hero. Such was the case with Taika Waititi, who was hired to breathe new life into Thor after the character's second solo outing, Thor: The Dark World, was met with a tepid response by both fans and critics.
In Thor: Ragnarok, Waititi weaponized star Chris Hemsworth’s charm and comedic timing (on full display in 2016's Ghostbusters) to turn Thor into a smiling, wise-cracking, even happy-go-lucky warrior. His bravado often backfired to make him the butt of jokes, knocking him on his ass more often than not. Ragnarok was in the middle of production as frequent Marvel screenwriters Stephen McFeely and Christopher Markus were outlining their massive, Marvel-spanning two-parter, Avengers: Infinity War and Avengers: Endgame.
"We already had outlined a draft of a sort of down on his luck Thor, 'Lebowski Thor,' but when we were in pre-production, Chris was in Australia and they were shooting Ragnarok and he was very excited about the new direction," Markus tells SYFY WIRE. "He got in touch with us to make sure that in the movie after that, it wasn't going to be a sort of radical — I don't think he'd read the script yet because we hadn't given it to him."
Given the drastic reimagining of the character between appearances, Hemsworth's concern was understandable. If fans grew to love the Thor that he and Waititi had crafted for Ragnarok (and they did), snapping him back to straight man in Infinity War and Endgame would be jarring and disappointing. Having not read the script for those two movies yet, Hemsworth took action.
"So he and Taika flew in, and they weren't even done shooting," Markus says. "They showed us some of the scenes they had and we went over the Thor scenes in the two movies and collectively thought about, okay, how is this new angle on Thor? How does he react to certain things?"
The result of the meeting was a natural arc for Thor — creating a goofier hero in Ragnarok made the path to sloppy, overweight mess a much gentler slope with a more obvious endgame. Hemsworth was protective of the character's new direction, not only because he had played him for so many years but because the change allowed him to stretch as an actor.
"For a guy like Hemsworth to play an overweight PTSD sufferer like that, that's gold for an actor," McFeely says. "That was interesting to him."
Given the careful architecture of the Marvel Cinematic Universe and the kind of future-looking collaboration that led to the new Thor, it'd be tempting to assume that all projects are carefully designed to set up future films and now, TV shows. That the entire second act of Endgame was built around traveling back to different key moments in past MCU movies to retrieve Infinity Stones only reinforces that presumption. But the screenwriters swear that those moments were not pre-selected; the entire sequence was an invention of necessity, not years of preparation.
"Because our third act is a huge fight, it was not a time for emotional repair. Ironically, going back in time allowed these characters to move forward," Markus says, pleased with the logline he created out of thin air. "Obviously there had to be an Infinity Stone [in each scene], but it came down to how much emotional content we could get out of where they went. We began to realize that each section, each stone path, in addition to being a little fun heist, it had to do emotional work and it had to do repair to the damage that you'd seen in the first act."
Similarly, the Disney+ shows that will come directly from Endgame — Loki escaping in 2012, Hawkeye reuniting with his daughter, Falcon and the Winter Soldier carrying on for Captain America — were not an endgame when they were writing the movie.
"Marvel just wants to make the best movie in front of them, and so rarely does anything get taken out of our arsenal because they have plans years from now — we didn't even know there was a Disney streaming," McFeely says. "I think at some point when the scripts were really coming together, Kevin must've said, 'Ah, now that there's a need for shows on the streaming platform, what should we do? What about Loki? How could that work?' And I don't know, to be honest. I don't know if they've even announced how Loki works, but my assumption is that it might have something to do with his cameo in Endgame."