At this point, the fourth Avengers movie is as far from our eyeballs as the eighth and final season of Game of Thrones. We've still got Black Panther, Infinity War, Ant-Man and the Wasp, and Captain Marvel before May 3, 2019.
Originally slated as Part 2 of Infinity War, Avengers 4 was changed to its own entity along the way, although it will definitely be affected by the struggle against Thanos (Josh Brolin) and even feature the Mad Titan in a major role. The connection between the two films is underscored by the fact that the Russo Brothers are shooting the movies back-to-back; Avengers 4 is expected to finish filming this summer.
We can only guess at what the plot might involve when it's more than a year to release, but set photos that have made their way online have people guessing that time travel could be an element of the story. Why? Pictures posted by JustJared.com show a long-haired, two-eyed Thor (Chris Hemsworth) chilling with Tony Stark (Robert Downey Jr.). However, last we saw the God of Thunder, his hair was closely cropped due to his stint as a gladiator on Sakaar in Thor: Ragnarok. More importantly, he had on an eye patch due to his fight against Hela (Cate Blanchett).
Another set of photos depict Captain America (Chris Evans) palling with Ant-Man (Paul Rudd) and the Hulk (Mark Ruffalo in a motion capture suit). The odd thing: Cap is wearing his original uniform that he donned during the first Avengers. The images also show the actors with strange, X-shaped objects that look like watchs affixed to their wrists, which might have something to do with keeping them all fixed to each other's locations or making sure they stay within a certain time period (if time travel's got anything to do with it).
Now, why would Thor have his old hairdo and both eyes while Cap's got on his old uniform? Could it mean that our heroes will travel through time in Avengers 4? It's not all that far-fetched when you consider that 1) Thanos will likely have the Time Stone by the time of the movie and 2) A Sorcerer Supreme like Doctor Strange (Benedict Cumberbatch) can manipulate time. They're basically one in the same since the Eye of Agamotto houses the Time Infinity Stone. Not to mention Tony Stark has dabbled in time travel over the years when looking to the comic canon, and could certainly be smart enough to build one.
On the other hand, it could be argued that these old school looks could just be the result of a massive flashback. But if that's the case, why is Cap wearing his first duds around Scott Lang when they didn't meet until Civil War? Yes, it's possible that his other suit is at the cleaners or something, but how cool would it be for the characters to interact with past versions of themselves? This would be a really fitting way to close out the MCU as we know it, by revisiting moments from the last 10 years. Basically like Avengers: Back to the Future.
It cannot be overstated that all of the time travel talk is pure conjecture right now, but based on the meager photographic evidence, it isn't a theory that just comes straight out of left field. The Avengers could go full Doc and Marty and stir up some trouble in the past. Ironically, we'll have to wait for the future to see if we're correct.