In October 2014, Marvel Studios wowed the world when they announced their slate for Phase 3. The first three phases of the MCU would come to a head in a two-part blockbuster event, Infinity War Parts 1 and 2. Of course, plans change though. Back then, Joss Whedon was still in the picture, whereas now the Russo brothers are in charge of Infinity War and Avengers 4. As a result, the fourth Avengers movie no longer seems to be a 'part 2'. The two films are still deeply connected, but they now seem like separate projects, even filming back-to-back rather than simultaneously (as originally planned).
We're Seeing Some Strange Signs
Of course, Infinity War promises to be a cosmic adventure like nothing we've ever seen before. The Avengers will team up with the Guardians of the Galaxy in battle against Thanos, the Mad Titan, and we'll see the Black Order launch a devastating attack on Earth. Interviews with Josh Brolin have made clear it that his character doesn't end the film in possession of all the #InfinityStones, and that Thanos's story will continue in Avengers 4.
In spite of this though, it seems as though Avengers 4 is rather more Earth-bound than we'd expected. A Japanese subplot is becoming ever more significant in scale, with recent reports suggesting that Hawkeye may take up the new identity of Ronin. Set photos revealed that Scarlett Johansson has been working on the Japanese set, while Marvel recently recruited Hiroyuki Sanada for an unknown (but likely connected) role.
To add to the surprising twists, Marvel recently issued a casting call for secretaries and female engineers from the '60s. These are most likely flashbacks of some kind as we've not yet had any indication that events in this time period held any relevance to the Infinity Stones. Although the casting call itself cautioned that these were very small scenes, flashbacks to the '60s are another odd element of Avengers 4. Whatever's going on, it seems unlikely that it has anything to do with a cosmic battle to save the universe from Thanos.
What's Going On?
Until now, the common assumption was that Infinity War would see #Thanos ravage the Earth, taking possession of at least the majority of Infinity Stones. As a result of this, many fans expected to see the Avengers and the Guardians of the Galaxy pursue him in Avengers 4 in order to wrest the Stones away from Marvel's greatest threat.
That no longer seems to be the case though. Too many scenes are clearly Earth-bound; the Japanese subplot is becoming too important, and these '60s flashbacks make no sense at all for a film with that context. Now, I'm sure Avengers 4 has a large cosmic element to it; Thanos is confirmed, and filming of those scenes would largely be green-screen, so we wouldn't see any set photos of him. But there's clearly something else happening in this film, something Earth-based, something that anchors the plot to our humble blue sphere. Avengers 4 doesn't look to be the purely cosmic adventure that we've all been expecting.
If that's true, then it would help clarify some recent comments by the director of Guardians of the Galaxy. James Gunn is currently writing the script for Guardians of the Galaxy Vol. 3, and believes this film will set up 20 or even 30 years' worth of cosmic Marvel stories. The clear implication is that Guardians will be the movie that opens the MCU up to wider cosmic implications, not Avengers 4. In fact, so far, the only movie we've been told that Avengers 4 sets up is the next Spider-Man film.
It looks as though Avengers 4 may well be something of a surprise to fans. This makes sense, given that #Marvel is currently refusing to reveal the title on the grounds it would be a spoiler. They've also publicly debunked the obvious title, Infinity Gauntlet, insisting that's not it. The House of Ideas seems to have something unexpected in the works.
Phase 3 has been jam-packed with twists that took fans and critics alike by surprise. Take the moment when Ego revealed that he'd killed Peter's mom in Guardians of the Galaxy Vol. 2, or the revelation that the Vulture was Liz's dad in Spider-Man: Homecoming. With #Avengers4 though, it seems as though we could be heading for the biggest surprise of them all...