Which Marvel movies will Avengers 4 revisit through time-travel? It's long been clear that the as-yet-untitled Avengers 4 is some sort of time-travel film. Set photos have shown a number of heroes in older costumes, while Paul Rudd was spotted on set in a scene evoking the Battle of New York. Leaks and rumors have supported this, suggesting that Earth's surviving heroes will visit the past in an attempt to rewrite history and avert the "snap."

It's a smart approach for Marvel to take, allowing the studio to resolve the cliffhanger of Avengers: Infinity War while celebrating the last decade's worth of movies. Given that many major Marvel actors' contracts are running out, it could serve as a final victory lap before big names leave the MCU for good.

Related: What Ant-Man & the Wasp's End-Credits Scenes Reveal About Avengers 4

It's still not clear why the Avengers are traveling through time, although it's widely assumed to be a direct attempt to stop Thanos; to claim the Infinity Stones before him to change the past or assemble an Infinity Gauntlet of their own. While the reasoning is unclear, we do have a sense of where. From set photos, strange costuming decisions and other rumors, here are the MCU movies it looks like we'll be revisiting.

The Avengers - the Battle of New York

The Avengers In New York

2012's The Avengers the most important movie in the MCU up to that point. This was the film that would make or break the entire shared universe model, finally drawing all the disparate elements together for the first time. It's crucial from an in-universe perspective, too, with the Avengers assembling in order to defeat an alien invasion. What's more, they did so in public, meaning the Battle of New York serves as a defining moment for superheroes; for the first time, humanity was forced to confront a reality of gods and monsters, aliens and super-soldiers.

There's abundant evidence that Avengers 4 is definitely revisiting the Battle of New York. The first hint was when set photos showed Tony Stark wearing the same Black Sabbath shirt he wore for most of that film. Significantly, his face was bruised, suggesting that scene was immediately after the heroes drove back the Chitauri army. This was then backed up by a number of set photos showing Thor and Loki in their classic Avengers-era costumes, all filmed at the same building as the Stark scene. One even showed Loki being taken away in chains, just as in the original movie. A final batch of set photos provided conclusive evidence, with Captain America wearing that "old-fashioned" uniform - standing next to an older Tony Stark and, most surprising of all, Ant-Man - this final piece pointed towards time travel.

The Avengers was the only time in the history of the MCU when two Infinity Stones were in the same place - Loki had possession of both the Tesseract (the Space Stone) and the Scepter (the Mind Stone) - so if the Avengers really are traveling back in time to collect the six, it would be a smart place to visit. The big question from all the photos, of course, is who's a time traveler and who's not?

Related: Avengers 4 Is Revisiting The Battle of New York - But How?

Guardians of the Galaxy

Gamora and Nebula of Guardians of the Galaxy

2014's Guardians of the Galaxy was another crucial movie for the MCU. While other Marvel films had flirted with the cosmic - most notably the Thor movies - they had done so by balancing time spent in space with scenes set on Earth. Guardians of the Galaxy, however, embraced this weird and wonderful side; it was a planet-hopping adventure populated by colorful and varied aliens (as well as Chris Pratt). In story terms, the film fleshed out Thanos' character and role a little bit more, for the first time explaining what the Infinity Stones were, hinting at their supreme and unlimited power.

This may be another film the team visits in Avengers 4. In September 2017, a number of Marvel actors - including Zoe Saldana and Karen Gillan - supported a charity campaign to help the victims of Hurricane Harvey. While most attention was rightly focused on the worthiness of this cause, eagle-eyed viewers also noted that both Saldana and Gillen were wearing versions of their costumes from Guardians of the Galaxy. There's only really one reason they'd be doing so; the actresses were filming scenes wearing those older costumes. Alongside them were Paul Rudd and Evangeline Lilly, although they likely came from the Ant-Man & the Wasp set.

Prior to Avengers: Infinity War, the Power Stone was only seen in Guardians of the Galaxy; hidden on Morag, then in the hands of various parties before the Nova Corp. hid it away on Xandar (where Thanos eventually stole it from). That makes the events of this movie the only time in recent history where the stone has been out in the open, and thus the best moment for any time traveling Avengers to visit. Because it's only suggested by costumes, it's hard to know specifics, although the presence of the then-antagonistic Gamora and Nebula suggests some troubles ahead.

Page 2 of 2: More MCU Movies Avengers 4 May Visit

Somewhere In The Thor Trilogy

Although Thor: The Dark World is hardly the most critically acclaimed Marvel movie to date, it's was crucial step along the road to Avengers: Infinity War. The film introduced the weirdest of the Infinity Stones, the Reality Stone, with Jane Foster becoming the unfortunate host for its power. This was also the last movie to truly explore Asgard before the Realm was destroyed in last year's Thor: Ragnarok.

Related: After Thor: Ragnarok, What's Next For Asgard?

During production of Avengers 4, Marvel filmed extensively at Durham Cathedral. Set photos showed fake doors bearing a familiar pattern - one seen in the halls of Asgard, during both Thor: The Dark World and Thor: Ragnarok. There was also a statue reminiscent of Thor's vision in Avengers: Age of Ultron. This suggests Durham will be, in some form, doubling for Asgard. And, as it's destroyed, that points towards going back in time.

It would particularly make sense for the Avengers to revisit the events of Thor: The Dark World. The Reality Stone was secreted away in so inaccessible a vault that it was only accessible during the Convergence of the Nine Realms. Asgard kept it for a short period of time, before deciding it was too dangerous to store two Infinity Stones at once, instead sending it to the Collector. In story terms, no doubt this would be a very emotional trip for the God of Thunder. He'd be traveling back to a time before Asgard's destruction, back when his father was still alive.

Captain America: Civil War (Possibly)

Captain America: Civil War - Frank Grillo as Crossbones

While 2016's Captain America: Civil War was key in the story development of the MCU, it doesn't directly link to any of the Infinity Stones (bar the Mind Stone in Vision's forehead). Still, it did see the Avengers torn apart, first by the Sokovia Accords and then by Baron Helmut Zemo, leaving the Earth was left more vulnerable than ever before.

Curiously enough, though, there is some evidence that Avengers 4 will revisit the opening of Civil WarHeidi Moneymaker, Scarlett Johansson's stunt double, posted an image on Instagram in which she celebrated the end of Avengers 4 filming. The costumes worn by Johansson is identical to what she wore in the opening scenes of that film during the action in Lagos. More recently, Frank Grillo teased a return despite Crossbones dying early on in Captain America 3. While it's possible Moneymaker used an old image and Grillo was trolling fans, they both link to the same scene.

Related: Avengers Theory: Thanos Time Traveled At The End Of Infinity War

Of course, even believing this, the question becomes why the Avengers would revisit the events of Captain America: Civil War. All the other time-travel jaunts appear to be related to Infinity Stones, but there were no Infinity Stones in Lagos; Vision didn't participate in that mission, so not even the Mind Stone was there. It is possible the Avengers attempt to rewrite history and prevent Crossbones's suicide bombing, avoiding their separation, which would be a more personal side to the mission.

More: Avengers 4 Shouldn’t Kill the Original Avengers

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