All Avengers 4 rumors and spoilers leaked so far

Directors Anthony and Joe Russo put out a joint plea (via Variety) ahead of the Avengers: Infinity War premiere, urging people to avoid social media and "the internet in general" until they'd had a chance to see it. By this stage, however, the majority of Marvel fans already knew way more about the movie than the studio would have liked, and we're seeing a repeat of that with the sequel, Avengers: Endgame.

Endgame became the most anticipated superhero movie of all time when the credits finished rolling on 2018's Infinity War, a film that left viewers with more questions than answers. Luckily — thanks to a combination of loose-lipped cast members, inside sources and leaked set images — we may already have the answers to some of these questions.

The release of the first Endgame trailer quelled some of the bigger rumors (speculation over the title of the movie was brought to an emphatic end), though it seemed to validate some major theories at the same time. If you plan on going into Endgame completely spoiler-free then we wish you the best of luck, but if you just can't wait for your Avengers fix, we've got all the leaks and rumors rounded up right here.

Captain America leads a new Avengers lineup

Fans should always question the authenticity of leaks, no matter how legit they may seem at first glance. In November 2018, images of the surviving Avengers (plus Rocket Raccoon and Nebula) decked out in matching suits began to spread across the internet like wildfire, but ComicBook.com later confirmed that they were bogus. The leaked concept art that preceded these images by a few months was likely the real deal, however.

In June 2018, an image of all the heroes that survived the Decimation being led into battle by Captain America leaked, giving away the new lineup. A beardless Steve Rogers is backed by fellow original Avengers Iron Man, Black Widow, Hulk, Hawkeye and Thor, who are joined by Ant-Man and War Machine. Newcomer Captain Marvel is also present, as are Rocket Raccoon and Nebula, daughter of Thanos. So is this the team that will take on Thanos in Endgame?

The fact that this leaked image looks very similar to the ones teased at San Diego Comic Con in 2017 was enough to convince most fans it was genuine, and the first Endgame trailer certainly strengthened those claims. The clean-shaven version of Cap seen on the leaked poster features prominently in the trailer. He's back in the suit he wore while working for S.H.I.E.L.D in Captain America: The Winter Soldier, though he remains without his signature shield. Chances are we'll see him tossing the old thing at some point, however, and here's why…

We'll time travel back to the first Avengers movie

The aforementioned leaked concept art became the subject of much scrutiny, and it didn't take long for someone to notice a discrepancy with Scarlett Johansson's hair color. Black Widow sported a blonde look in Infinity War and she's got the same hairdo in the Endgame trailer, yet in the leaked image she's gone back to being a redhead, the same style she had around the time the Battle of New York took place. Does this mean we're going to revisit this pivotal moment?

Set photos obtained by Atlanta magazine reveal that Marvel has built a new set in the area, though it isn't really a "new" set at all. "The scene is an almost perfect recreation of the moment from [2012's The Avengers] where Nick Fury warns Tony Stark that a nuclear bomb is on the way to Manhattan," CBR confirmed. "Importantly, there is a late model sedan which has the exact same damage done to it as when Iron Man crashed into it in The Avengers."

Pictures of Chris Evans on set in the suit he wore in The Avengers have been circulating online since early 2018, courtesy of Just Jared. The Endgame trailer revealed that Cap will be in his Winter Soldier gear in the fourth Avengers outing, so is this confirmation of time travel? It could technically be a flashback, but the wrist devices worn by Rogers and company (via the Express) suggest that Earth's Mightiest Heroes are indeed jumping through time.

Hawkeye will become Ronin

It was one of the biggest reveals in the first Endgame trailer, but it wasn't exactly a surprise; fans have suspected that Hawkeye would be returning as Ronin for well over a year now. In October 2017, behind the scenes images of Jeremy Renner dressed in what is unmistakably Ronin attire found their way onto Chinese website Weibo (via ScreenRant), all but confirming that Clint Barton was shedding the Hawkeye moniker. It's clearly happening, but is there comic book precedent for it?

In 2007's New Avengers #30 (via CBR), Barton hangs up his bow and goes on a journey of self-discovery that takes him to Japan. It's here that he learns how to fight with swords and becomes known as Ronin (a Japanese term for a wandering samurai with no master). Last we heard, movie-Barton had cut a deal with the government to protect his family after the events of Captain America: Civil War, so why would he go rogue?

There's a high chance that the Barton family vanished during the Decimation, as the voice over in the trailer seems to hint at. "We lost family," Steve Rogers says as Black Widow discovers Barton standing over a bunch of bodies, "we lost a part of ourselves." He's quite clearly in Japan, but what business does Barton have in the country's neon-lit capital? "The rumor is that he's working as Ronin in Tokyo and hunting down Yakuza, who are actually Skrulls," MCU Cosmic reports.

Tony Stark builds his own Infinity Gauntlet

There were so many leaks and rumors about what would go down in Avengers: Infinity War before the movie was released that, by the law of averages, some would inevitably turn out to be correct. When it comes to a 4chan user by the name of Anonymous, however, there seems to be more than just luck involved. Anonymous successfully predicted a staggering amount of Infinity War's plot, including the fact that Thanos would sacrifice Gamora to obtain the Soul Stone and the shocking return of Red Skull. In May 2018, the same user posted a detailed run-down of plot points for Avengers 4, which in which a rumor surfaced that Tony Stark will build his very own Infinity Gauntlet.

"Iron Man reassembles the Avengers and decides to build his own Infinity Gauntlet to undo everything that Thanos did," Anonymous wrote (via the Express). "They recruit Ant-Man to help them travel through time and space using the Quantum Realm to retrieve the Infinity Stones from different time periods. Thanos finds out about their plans and becomes hellbent on stopping them. The movie revolves around the relationship between Captain America and Iron Man." Of course, this is nothing but unconfirmed rumor right now, but given the source's track record, it can't be ignored.

Professor Hulk will wield the 'Stark Gauntlet'

What's going on with the Hulk? It was one of the biggest questions post-Infinity War, which (aside from the beating he took from Thanos right at the start) the big green guy was conspicuously absent from. Bruce Banner (Mark Ruffalo) was unable to transform into Hulk after he escaped Thanos with a helping hand from the now departed Heimdall, so where is all this leading? If the Avengers 4 rumors inspired by the leaked concept art are anything to go by, it's leading right to Professor Hulk.

One of the things about the leaked image that really stands out is the fact that Hulk is wearing clothing. Not only that, but his facial expression speaks volumes — he looks far more human than ever before. It seems as though Banner will finally figure out how to co-exist with the Hulk, and in doing so he becomes Professor Hulk. This version of the character (who has all the physical attributes of the Hulk but retains the mind of Banner, minus the anguish) was born out of Peter David's epic run on The Incredible Hulk.

The Professor Hulk theory checks out with 4chan tipster Anonymous, who predicted (via the Express) that Hulk will have a huge role to play in the coming rematch against Thanos. "Hulk's subplot centers on Banner and Hulk finally merging to become Professor Hulk. He is the one that ultimately wields the Stark Gauntlet against Thanos, losing his arm in the process."

Iron Man has a kid

Seeing as this Avengers 4 leak came directly from the mouth of Gwyneth Paltrow, it seems almost certain that Tony Stark will be a daddy by the time we catch up with him in Avengers 4. Speaking during an interview for the official Avengers: Infinity War magazine (via ComicBook), she revealed that her character, Tony Stark's longtime love interest Pepper Potts, was destined to become a mother.

"Pepper and Tony have had a real long journey together," Paltrow said. "She obviously starts as his dutiful assistant, and then the relationship evolves, and now this decade later they're married, and they have a child. Their relationship has evolved in all of the ways that great romances evolve."

The first question raised here is, "How did this spoiler make it to print in an official Marvel magazine?" The second question is, "Does this mean there's going to be a time jump?" We can't answer either definitively, but the fact that Paltrow has said she's going to become Mrs. Stark and have a child by Tony does imply that we will rejoin Earth's Mightiest Heroes at least a few years after the devastating events of Infinity War.

The death of Tony Stark

If Tony Stark does have a child in Avengers 4, the kid is going to grow up without a father. At least, that's what a recent leak detailing the supposed plot of the upcoming sequel to Spider-Man: Homecoming suggests. A Redditor claiming to have connections with "a reliable source" has reportedly been told that the second Spider-Man solo outing will open with Peter Parker mourning the loss of Mr. Stark. The plot will revolve around "something groundbreaking that Stark has created, and which is stolen and Spider-Man must retrieve," AHarbingerOfStuff writes.

There's a separate fan theory getting a lot of love on Reddit that also predicts the demise of Stark in Avengers 4. ElephantErik's post (which has been upvoted over a thousand times) claims that Stark doesn't need to create a new Infinity Gauntlet, as he's essentially a living one. "He is a living container and would be able to contain a massive energy source in his arc reactor outlet. Infinity War even makes a point in the park scene with Tony and Pepper to show him retaining his arc reactor even though he doesn't really need it anymore."

The poster claims that Stark will be able to contain and utilize the Infinity Stones with his arc reactor, but will die using them to defeat Thanos. "Stark has been trying to undo all his mistakes and continually tries to atone for them," the Redditor added. "His sacrifice would complete his arc of atonement."

There'll be a scene with 'every character' in it

Navigating the press can be tricky when you're a Marvel star. A comment that might seem pretty innocuous to an actor will inevitably be analyzed at length by fans, who do sometimes have a tendency to jump to conclusions. Sebastian Stan's comments in April 2018 didn't need much decoding, however. He dropped one of the bigger spoilers in the run-up to Infinity War, revealing that there will be a huge scene that involves every character.

"There was one scene, I think, we had where everybody was there," Stan said (via ScreenRant). "I can't really talk about that scene, but I knew it took them three months in planning this scene to have everyone there. You look around and you just saw everyone from Samuel L. Jackson to Michael Douglas to Michelle Pfeiffer. Everybody was there."

Scarlett Johansson (Black Widow) has also alluded to a huge coming together of Marvel heroes in Avengers 4. During an appearance on The Late Show with Stephen Colbert, Johansson discussed filming a scene that she believed could have featured up to 32 characters. "There's so many of us, I don't even know who's a Marvel character and who's like a crew member," she joked.

Pepper Potts set to suit up

Gwyneth Paltrow has all but confirmed that Pepper Potts will be suiting up in Avengers 4. She briefly donned Iron Man's Rescue Armor in Iron Man 3 when she came to his aid during the attack on his Malibu mansion, and Paltrow's Instagram feed suggests that she will do the same in the upcoming Phase Three closer. In a 2017 post that she's since had the sense to make private, the Oscar winner shared a picture of herself getting a foot massage on set (via CBR), giving away a big spoiler in the process. 

Paltrow's lower legs are visible in the picture, and she's quite clearly wearing a motion capture suit. She didn't turn up in any kind of CGI getup in Infinity War, so the only logical explanation is that she was filming scenes for Avengers 4 at the time. Paltrow seemed to confirm she'd be in full costume this time out during her January 2018 appearance on The Late Show with Stephen Colbert (she admitted she'd been wearing a body suit with ping pong balls on it), and we now have some actual photo evidence.

In what appears to be a selfie from the set, a supposed leaked image of Paltrow posing in front of a green screen in full Rescue mode is making the rounds online after being shared by Uncanny Comic QuestThe fan art wasn't far behind, but we'll have to wait until April 2019 to see Paltrow in full superhero flow.

Characters confirmed to be coming back from the dead

The fact that Tom Holland's Spider-Man and Chadwick Boseman's Black Panther were wiped out by Thanos despite both having sequels on the way pretty much confirmed that some (if not all) of the departed heroes will be brought back to life in Avengers 4. Directors Joe and Anthony Russo have been doing their best to throw us off the scent by implying that the mass deaths at the end of Infinity War are permanent, though it's hard to keep up that pretense when many of the actors themselves are contradicting them.

"I got a lot of texts saying, 'I can't believe you're dead, your character is dead,'" Drax actor Dave Bautista said (via MovieWeb). "They were really like heartbroken and I was like, 'I'm gonna be in four, I'm gonna be in Guardians 3.' I don't know how they're bringing me back, yeah but somehow I'm going to make it because, as far as I know, I am going to be in Guardians 3, so I have to be back." Drax's Guardians colleagues Star-Lord and Gamora are also rumored to return.

Zoe Saldana told E! Live From the Red Carpet (via ComicBook) that being sacrificed by her father/abductor Thanos felt like a "see you later" rather than a formal goodbye. "I knew that we will have to all come back, at some point this fall, and finish up the fourth installment of Avengers." Letitia Wright (Shuri) has added to the Avengers 4 spoilers, confirming that she and Chris Pratt are also returning.

Did the Endgame trailer confirm the time travel theory?

The film itself took place before Thanos got his hands on all six Infinity Stones, but his and Ant-Man's arcs crossed over in devastating fashion during the Ant-Man and the Wasp post-credit tags. The Decimation takes place while Scott Lang is inside the Quantum Realm, leaving nobody to pull him out. The fact that Janet van Dyne conveniently warned Lang about time vortexes before he entered the Quantum Realm sparked rumors that these previously unmentioned portals would play a big role in Endgame, and the first trailer strengthened that theory considerably.

After this ominous time vortex warning from the original Wasp (and not to mention the leaked Battle of New York set photos), people were always going to study the Endgame trailers for signs of time travel, and some believe they may have already found one. According to ComicBook.com, fans are convinced that the footage of Lang being viewed by Captain America and Black Widow is the first evidence, because the word "archive" can be see in the corner of the monitor.

Lang shows up at the Avengers facility with the van containing Hank Pym's streamlined quantum tunnel in tow. The fact that Steve Rogers immediately asks whether this is an "old message" has people convinced that Ant-Man has accidentally popped out of a time vortex into the wrong year. Black Widow's vague response is supposedly only there to throw viewers off the scent, something the Russos admitted they were guilty of while promoting Infinity War.

Is Nebula the main villain?

Nebula (Karen Gillan) has been on the periphery of events so far, but the daughter of Thanos could turn out to be a crucial player in Avengers 4, with her arc potentially coming full circle. She started out hating adopted sister Gamora, but they reconciled before she was killed by their so-called father in Infinity War. The third Avengers outing borrowed heavily from 1991's The Infinity Gauntlet, and Nebula plays a huge part in the conclusion of that title.

In the six-issue series, the Luphomoid assassin is captured by Thanos and sadistically tortured (a moment we've already seen play out on screen in Infinity War). She's the one who's eventually able to turn the tables on Thanos, stealing the Gauntlet from him. The problem is, Nebula is so messed up at this point that she ends up being even worse than Thanos with the Gauntlet, forcing the intergalactic warlord to team up with the Avengers in a bid to stop her.

It's hard to see Earth's Mightiest Heroes joining forces with Thanos after all he's done, but Gillan is all for staying true to the source material. "When I was preparing to play Nebula the first time, I read The Infinity Gauntlet," she told ScreenRant. "I loved it because it was like the most Nebula-heavy comic." Saying it would be "amazing" if the movies were to follow that same arc, she added, "I don't know yet — very big secret. But I'm hoping."

Shuri becomes the new Black Panther​​

Wakanda made a valiant attempt to halt Thanos' invasion of Earth in Infinity War, but the fictional African nation sustained devastating losses in the process, and that was before the Mad Titan even used the Infinity Gauntlet. King T'Challa was one of the unlucky souls turned to dust when Thanos snapped his fingers, leaving Wakanda without a leader going into Avengers 4. The stage seems set for T'Challa's younger sister Shuri (Letitia Wright) to accept the Black Panther mantle and rally her people for round two with Thanos.

There's comic book precedent for this. In Reginald Hudlin's 2009 Black Panther series, T'Challa falls into a coma after a battle, and Shuri takes over as the Black Panther. Her brother later recovers, leaving Wakanda with two Black Panthers, a premise that ScreenRant predicts could well unfold in the planned Black Panther sequel. According to ComicBook.com, this Shuri rumor is gathering pace with Marvel fans, and Wright herself has expressed an interest in following Hudlin's story.

"If the opportunity came about, then why not? It would be comic book accurate," she told ScreenRant. "Yeah, that would be amazing. It means more training, more learning and it would really be an amazing adventure [...] I'm excited!" Recently revealed concept art confirms early designs for Shuri's Black Panther costume already exist, so it's starting to look like a matter of when she'll become the new Black Panther, not if.   

Thanos loses his head, literally

If the opening of Marvel's new event series Infinity Wars Prime is anything to go by, we might get to see Thanos lose his head in Avengers 4, and we're not talking about a crack in his normally calm demeanor. In the comic, Thanos meets his end at the hands of a mysterious masked villain named Requiem, who beheads him with one powerful swing of her sword. "Little is known about this new character," ComicBook.com reports. "She has been described as an angel of death… Anyone who can kill the Mad Titan with a single blow is surely someone to be feared."

Of course, there's no Requiem in the Marvel Cinematic Universe (not yet, at least), but that doesn't mean the comics aren't foreshadowing the films. "You may recall in the [Infinity War] movie how Thanos told Thor 'You should have aimed for the head' when they were in a battle, and we can't help but think there could be some connection there with this story," SyFy said. "The visuals from the epic death scene in the comic are certainly some that we would love to see repeated on the big screen, especially if Thor or any of the others somehow get a chance of having another swing at him."

Thor is certainly a contender, but one of Thanos' so-called daughters is far more likely to strike the killing blow. In fact, CBR is predicting that new comic creation Requiem could actually turn out to be Gamora in disguise.

Red Skull isn't done chasing the Infinity Stones

Not many people expected to see Red Skull pop up in Infinity War, but it turns out this nazi-sympathizing villain has closer ties to the MCU's overarching plot than we realized. Real name Johann Schmidt, the former HYDRA boss was the main antagonist in 2011's Captain America: The First Avenger, but he vanished at the end of that movie after touching the Tesseract. His whereabouts became a mystery, but we now know exactly where he ended up.

When Thanos arrives on Vormir in search of the Soul Stone in Infinity War, he discovers that Red Skull has become the stone's guardian. "A lifetime ago, I too sought the stones," Schmidt tells the Mad Titan. "I even held one in my hand. But it cast me out, banished me here, guiding others to a treasure I cannot possess." Thanos acquires the Soul Stone by sacrificing the person he loves most, Gamora. Now that he has it, is Red Skull free to go about his business? According to the Russo Brothers, he is, and his hunt for the Infinity Stones might not be over.

As part of Vudu's Infinity War viewing party, the sibling filmmakers took questions from fans, one of whom asked about Red Skull's future. "Red Skull is free to leave Vormir, and he is also free to pursue his desire for an Infinity Stone," they confirmed. Could he still have a part to play in Avengers 4?

Are the 'dead' Avengers in a parallel universe?

There's a popular theory that all the dead Avengers (and everyone else that vanished when Thanos used the Infinity Gauntlet) are actually trapped in a parallel universe inside the Soul Stone, and there's comic book precedent for this. In the source material, the Soul Gem (as it's called in the comics) houses the Soulworld, a pocket dimension that acts as a kind of purgatory. The orange-tinged, dream-like scene in which Thanos talks to young Gamora after her death in Infinity War may take place inside the stone, meaning the Soulworld exists in the MCU in some form — and according to Digital Spy, there may have been a hint that this is indeed the case during Ant-Man and the Wasp.

When we catch up with Scott Lang in the sequel, we discover that he's been learning magic to combat his boredom during his house arrest (imposed on him for helping Captain America in Civil War). In one scene, his onscreen teacher can be heard saying: "Snap your fingers. That gets them to look over there. Now that's misdirection. Easy-peasy." Is this a throwaway line, or a clue that Thanos has pulled off a grand misdirection of his own?

The Science Bros recruit a new member

Sometimes, it isn't what a Marvel actor says that gives the game away, it's where they say it. In August 2018, an observant Twitter user (via Metro) noticed that one behind-the-scenes interview with Robert Downey Jr. seemed to take place on the set of Shuri's lab in Wakanda. The tweet (which has since been deleted) pointed out that the backdrop was clearly the same, which surely means Stark is going to meet the young Wakandan genius. Of course, he has to get back to Earth first.

The first Endgame trailer opens with a desperate Stark recording a goodbye message for Pepper Potts aboard the Benatar, the ship that was being used by the Guardians of the Galaxy before Thanos wiped most of them out. He's been out of food for days and doesn't have much oxygen left, but we all know it's a case of "when" Iron Man is rescued, not "if." Once home, it looks like he and Shuri (and probably Bruce Banner, who's already in Wakanda) will combine their considerable brainpower and scientific knowhow to give the Avengers a chance to put things right.

Marvel threw a curveball during the Endgame trailer by having Shuri's face flash up on one of Bruce Banner's monitors, implying that she was lost during the Decimation. The thing is, Angela Bassett (Queen Ramonda) has already confirmed that she and Shuri both survived, even hinting at her daughter's importance going forward. "She's a bright girl there in Wakanda," Bassett said (via ScreenRant).

Mantis reveals meeting with Okoye and Captain Marvel

When Pom Klementieff, who plays Mantis, sat down for an interview with Paper magazine, she clearly thought it was okay to let her guard down a little. Marvel actors are schooled in the art of secrecy and know how to keep their lips sealed when they go into interviews with the movie media, but Klementieff accidentally let a spoiler slip when the fashion mag asked her a question about Time's Up. Captain Marvel star Brie Larson has been a leading figure in the movement, urging women to sign a statement of solidarity

"I remember Brie Larson coming to me and Danai Gurira on the set of The Avengers and she told me about the [Time's Up] letter to sign, and I found it really amazing to have all these women — and men too — together in fighting for a better world," Klementieff said (via ComicBook.com). "Things need to change, so it's great that we women are united and speaking out now."

By mentioning that she was on set with Larson and Gurira (the latter of whom plays Okoye), Klementieff not only revealed that there's a scene involving all three of them in the upcoming Avengers sequel, she roundabout confirmed that her character will be coming back from the Snap. Mantis was one of the many heroes turned to dust by Thanos in Infinity War, and while it's pretty much common knowledge that his actions will be somehow reversed in Avengers 4 at this point, we now know for sure that Mantis will return.

The Avengers will face an even greater threat

Thanos will return in Endgame, but will he be the lead villain? Tie-in toys have been a pretty solid source of Marvel spoilers for years now; they like to get them designed early, meaning manufacturers are often made privy to crucial details. ComicBook.com shared a picture of what appears to be some official Endgame merch long before the movie even had an official title, dropping a potentially huge spoiler in the process.

The packaging showed Thor and Rocket Raccoon kitted out with brand new matching costumes (the same costumes that inspired this fake concept art) which was exciting enough in itself, but it also included a short synopsis that seemingly confirmed a new villain would come to the fore in Endgame. "The Asgardian Thor wields the mighty Stormbreaker in his battle against new foes," the synopsis reads. "Rocket teams up with a new crew to guard the galaxy from an even greater threat." Who or what could this "greater threat" be?

We've already covered the possibility of Nebula as the main antagonist, whereas ScreenRant believes that the Celestials will emerge as the true big bads of the MCU during Endgame. The first Endgame trailer (via IGN) makes a point of showing us how Thanos has literally hung up his armor, using it as a scarecrow just like he did in 1991's Infinity Gauntlet. The six-issue event ends with Thanos choosing a quiet life as a farmer over his former career as an intergalactic warlord.

Frank Grillo's Crossbones is back

One of the biggest surprises in Avengers: Infinity War was the return of Red Skull, and it appears as though its upcoming sequel will bring another Captain America villain back with a bang. Speaking to the UFC Unfiltered podcast (via The Hollywood Reporter) in October 2018, Crossbones actor Frank Grillo revealed that the deadly assassin and HYDRA agent was going to be making an appearance in Avengers 4, but how is this possible? After all, Crossbones died when he tried to suicide bomb Steve Rogers, right?

"He makes an appearance in the next Avengers movie, but it's a flashback," Grillo explained, throwing caution to the wind. "I'm allowed to say whatever I want because I'm never doing another Marvel movie… I'm 117 years old." He didn't reveal which moment the Russos would be taking us back to, but the smart money is on his death scene. Grillo first appeared as Crossbones (real name Brock Rumlow) in 2014's Captain America: The Winter Soldier, though his contribution to that film doesn't really have much sway on the overarching plot of the MCU. When he faced off against Rogers in Captain America: Civil War, however, it changed everything.

Rumlow attempts to take Rogers out by blowing them both up, but Scarlet Witch is able to save Cap. Unfortunately, she accidentally kills dozens of innocent people in the process, which leads to the Sokovia Accords and the eventual break-up of the Avengers. Why Earth's Mightiest Heroes need to revisit this pivotal moment remains to be seen.

Return of the B.A.R.F?

When Frank Grillo dropped his big Crossbones spoiler during his interview on UFC Unfiltered (via The Hollywood Reporter), people began to react to the news that Crossbones was back, but not everyone picked up on the potentially critical language that he used. The fact that Grillo (perhaps best known for his starring role in The Purge: Anarchy outside of his Marvel movies) described the scene in question as a flashback speaks volumes, as most of the rumormongers and theory crafters have been working on the assumption that time travel will be involved in Avengers 4.

Of course, this could still be the case. Grillo might have simply used "flashback" for want of a better word, but it does raise an interesting question — what if there isn't much (if any) time travel and the scenes from the past are being revisited via Tony Stark's B.A.R.F technology? On top of this scene with Crossbones, we know that the Avengers will be revisiting the Battle of New York from the first movie, another pivotal moment for Cap and crew. At this point, most people seem to have accepted that Earth's Mightiest Heroes will be traveling back in time to that epic battle, but there's a chance they could just be seeing it unfold through Stark's gadget.

Rumors that B.A.R.F will return have been making the rounds since January 2018, when a set photo showing an orange case with the words "Binarily Augmented Retro-Framing" written across the front appeared on social media. Only time will tell.

Katherine Langford is playing a mystery character

In October 2018, TheWrap exclusively revealed that 13 Reasons Why star Katherine Langford had joined the cast of the upcoming Avengers sequel in a mystery role, and various other media outlets quickly backed the story up. "Langford has filmed scenes for the currently untitled Avengers 4," The Hollywood Reporter confirmed. "Character details were not available, and Marvel Studios had no comment." MovieWeb sources claim that Langford has already finished all of her filming for the movie, suggesting that she was brought on board in a relatively minor role and did what she needed to do during the September 2018 reshoots.

Langford's part clearly won't be a big one, but if it was little more than glorified extra work then Marvel surely wouldn't have gone to the trouble of hiring an in-demand star. She got a much-deserved nod at the Golden Globes 2018 for her work as Hannah Baker in teen drama 13 Reasons Why, the first season of which was a big hit for Netflix. The second season wasn't received anywhere near as positively, but the streaming service knows a star in the making when it sees one.

After Avengers 4 you'll be able to catch Langford in Cursed, an Arthurian fantasy from Sin City creator Frank Miller and Tom Wheeler, writer of 2017's The Lego Ninjago Movie. According to the Netflix press release, Langford will play Nimue, a "teenage heroine with a mysterious gift who is destined to become the powerful (and tragic) Lady of the Lake."

The Ancient One makes an unexpected return

Hot on the heels of Frank Grillo revealing that Crossbones was going to be appearing in a flashback during Avengers 4Michael Grillo (an executive producer on Ant-Man and Avengers: Infinity War) dropped another huge character spoiler. Speaking alongside Avengers 4 screenwriters Christopher Markus and Stephen McFeely on a panel at the 2018 Austin Film Festival, Grillo accidentally revealed that one presumed dead Doctor Strange character is being brought back.

With so many moving parts, organizing a production the size of Avengers 4 is no mean feat. The amount of big Hollywood actors involved is staggering, and Grillo was more than willing to discuss just how crazy it was trying to secure dates and line up schedules. Unfortunately for the producer, he accidentally let slip that the Ancient One would feature in Avengers 4 in some capacity. "When we got Tilda Swinton, she was just a one-day availability," Grillo said (via Super Bro Movies).

The Ancient One appeared to be fatally wounded during Doctor Strange, passing on after giving the titular sorcerer one last pep talk for his repetitive showdown with Dormammu. As she wasn't one of those killed during the snap, the Ancient One probably won't be brought back to life, but the remaining heroes could well pay her a visit in Avengers 4. Time travel is heavily rumored to be integral to the plot of the film, and as Swinton's character was the guardian of the Time Stone prior to her death, she could have vital intel for the team.

Has Erik Selvig seen the future?

Thor: The Dark World is generally considered one of the worst MCU movies to date, but according to a popular new Avengers 4 theory this seemingly inconsequential installment was actually far more important than we initially realized. When we catch up with Stellan Skarsgård's Dr. Erik Selvig in the 2013 sequel, we discover that he's been through something of a mental breakdown since being exposed to the Mind Stone by way of Loki's scepter in The Avengers (2012). After running around Stone Henge butt-naked shouting about saving people, Selvig ends up in a hospital, where he scribbles some rather interesting things on a chalkboard.

At the time we all took these scribbles for simple Easter eggs rather than long-game foreshadowing, but looking back now it appears as though the Scandinavian astrophysicist predicted the existence of the multiverse and may have even been aware of Thanos. The words "616 Universe" can be seen right above his head and there's a reference to "the Fault," which, in the comics, is a rift in the space-time continuum that has ties to the Mad Titan.

This in-depth fan theory links the various clues hidden on the chalkboard to events that would later take place in Thor: RagnarokAnt-Man and the Wasp and Avengers: Infinity War, painting Selvig in a whole new light. Could he yet have a part to play? Skarsgård isn't named on the Avengers 4 cast, but his character has been confirmed as alive — he's featured in the book Marvel's Avengers: Infinity War: The Cosmic Quest, Volume 2: Aftermath.

The death of Steve Rogers

Marvel fans have been predicting his death since 2016's Civil War, and Steve Rogers remains the most likely high-profile casualty going into Avengers 4. Chris Evans has now completed his contractual obligation to Marvel and he appeared to confirm he was hanging up the vibranium shield in an emotional tweet. "Officially wrapped on Avengers 4," the actor said on October 4, 2018. "It was an emotional day to say the least. Playing this role over the last 8 years has been an honor. To everyone in front of the camera, behind the camera, and in the audience, thank you for the memories! Eternally grateful."

Understandably, most people took Evans' tweet as a fond farewell to the character and a flood of articles followed, forcing the actor to clarify his comments. "I know I did tweet something that made a lot of people think that it was in some way a spoiler, and I should clarify that, regardless of how Avengers 4 ends, I would've tweeted the exact same thing," he said during a panel at Chicago's ACE Comic Con. "I know it had a ripple effect, but I am neither confirming nor denying anything."

In November 2018, Joe Russo told the Associated Press (via USA Today) that we haven't seen the last of Evans as the Star-Spangled Avenger. "He's not done yet," the co-director said. "I won't explain what that means but fans will soon understand what I'm talking about." Is Russo hinting at cameo flashbacks, or have rumors of Rogers' demise been exaggerated?

The Eternals could make a surprise appearance

A product of the great Jack Kirby's imagination, the Eternals are a superpowered race created by the godlike Celestials, beings like Ego the Living Planet. Kevin Feige confirmed that an Eternals movie was in the early stages of development when he spoke to The Wrap in April 2018, but there's been a lot of movement since. Marvel approved a script turned in by Matthew and Ryan Firpo and the studio chose Chloe Zhao to direct (via The Hollywood Reporter), with a 2020 release date being touted.

The Eternals look set to loom large over Phase 4, but could they appear before then? The Eternals movie is already casting (That Hashtag Show had the scoop on the character lineup) and according to DanielRPK of SuperBroMovies, that's because Marvel want a couple of them to show up in Endgame. "They may have a cameo or — most likely — they show up in a post-credits scene," he tweeted. "They will most likely show up in a cosmic Marvel movie so either Captain Marvel or Avengers 4 — A4 is more likely."

He alleges that the studio want to tie down actors for characters named Karen and Piper, who ScreenRant claim may be a gender-swapped version of Sprite. But what business would they, or any of the Eternals have in Endgame? The truth is they already have a player in the game — Thanos is an Eternal, though he possesses the Deviant gene, making him an outcast among his kind.

Who will rescue Iron Man?

The first Endgame trailer revealed that Tony Stark had managed to escape Titan using the Benatar, but how on Earth will he get home? Chances are Marvel will keep the details of his rescue under wraps so as not to spoil what could well be the opening scene of the movie, but it doesn't take a genius to figure out that Stark isn't going to die in space, despite his seemingly hopeless predicament. When we catch up with him in the trailer, he's recording a message for Pepper Potts using his battered Iron Man helmet.

"Just for the record, being adrift in space with zero promise of rescue is more fun than it sounds," Stark says. "Food and water ran out four days ago, oxygen will run out tomorrow morning, that'll be it." There are already plenty of theories about who will save Stark from certain death, from Nebula (who seems to aboard the Guardians of the Galaxy's ship with him) to Captain Marvel. But what if the trailer actually contained a clue?

We've already covered Pepper Potts donning the Rescue Armor in Endgame, and the way that Stark leaves a beat before the world "rescue" during his goodbye message to her could be a huge hint. As Nerdist points out, Potts was able to read a message sent between Stark's masks in Iron Man 3, which only she was able to access via retinal scan. IGN is also predicting that Potts will come to the rescue.