Although Marvel seems to be keeping it silent on what Avengers 4 has in store for us, a few set images prompted a lot of speculation. From 1940s cars being photographed to a scene showing Chris Evans wearing the Captain America in The Avengers, it has been assumed that Avengers 4 will have time travel in its story. This idea was broached with Avengers: Infinity War and Avengers 4 directors Joe and Anthony Russo. They like this kind of “technique,” and hinted that there might be another explanation for the scenes. Anthony Russo has this to say:
“It’s interesting, because yes, there are photos that always leak, and then there’s lots of conjecture about what those photos mean. Certainly, there is a five-minute sequence in Civil War around a piece of technology that was laid in for a very specific reason. So if you go back and look at that film, you may get a hint as to a direction.”
The technology that Anthony Russo was referring to is Binary Augmented Retro-Framing which Tony Stark had presented at MIT in Captain America: Civil War. He had shown the audience the last time he saw his parents before they died on December 16, 199. Rather than having Tony Stark and some other characters go back in time, the Russos had suggested that it is through B.A.R.F. Captain America: Civil had given us just a taste of this technology.
This is not the first time it has been indicated that B.A.R.F. will be used in Avengers 4. It had been rumored that there is a scene where Tony Stark is running a simulation with Harley Keener in order to study Battle of New York and find out a how to use the Tesseract against The Mad Titan. While B.A.R.F. can explain how some of the events are revisited, this technology works off memories, and Tony Stark had not been around for the battle against Crossbones in Lagos.
Avengers 4 will release on May 3, 2019, and Avengers: Infinity War will release on May 4.