The Avengers: Endgame trailer has plenty of mystery, but it's already hinting at the presumed time travel plot. After all of the suspense and build up, Marvel Studios finally debuted the trailer for Avengers 4 and gave anxious fans the first look at the culmination of the MCU. The launch was rumored but never confirmed, allowing for the surprise to manufacturer hype for a very somber teaser.

Even without any prior marketing, what Marvel set up in prior movies, set photos, and even several rumors helped provide plenty of evidence to support the belief that Avengers: Endgame is going to involve time travel. Shots from production showed a recreation of the Battle of New York from The Avengers, with Robert Downey Jr. wearing the same Black Sabbath shirt, Chris Evans in the redesigned Captain America outfit, and Chris Hemsworth once again sporting Thor's long hair. This could easily be for a flashback or use of the Binary Augmented Retro-Framing (B.A.R.F.) technology introduced in Captain America: Civil War. But, it was future photos of Ant-Man (Paul Rudd) also present for the battle that further showed Marvel's hand.

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There have even been rumors from casting that point to time travel being in Avengers 4. Emma Fuhrmann joined the cast in secret and has been rumored to be playing an older version of Ant-Man's daughter Cassie Lang. Some thought this could be explained through a time jump, but the Avengers: Endgame trailer doesn't indicate time jump of any sort. If Fuhrmann is an older Cassie Lang, then it would signify the heroes traveling not only back in time, but also to the future.

The biggest piece of in-universe evidence for time travel though came in a line of dialogue in Ant-Man and the Wasp's mid-credits scene. Janet van Dyne tells Scott to watch out for "Time Vortexes" when he goes back into the Quantum Realm. When he enters and is left stuck in the realm thanks to Thanos' snap killing Janet, Hank Pym, and Hope van Dyne, these vortexes were theorized to be his way out. And, even though Avengers: Endgame's trailer doesn't blatantly show the heroes at a different point in time, it does tease the film's time travel nature on more than one occasion.

Ant-Man Archive Footage

Scott Lang on camera in Avengers Endgame

The final scene of the Avengers 4 trailer shows Captain America and Black Widow (Scarlett Johansson) watching security tape footage from around Avengers HQ. The cameras show Ant-Man has escaped from the Quantum Realm and is now visiting the base of operations to see if anyone is inside. He says, "Hi, is anyone home? This is Scott Lang. We met a few years ago at the airport, in Germany, and I got really big." When this clip comes up on their screen, Cap immediately asks, "Is this an old message?", to which Black Widow responds by saying, "It's the front door." This seems to indicate that this is indeed a new message, but a closer look may show it's newly discovered but an old message.

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In the top left of the video footage, it's tagged as being "archive" footage, meaning this video is not from a live feed. This would indicate that this is something that happened at a previous point in time, while still making this the first time that Cap or Black Widow are seeing this footage. But, if that were the case, then how come no one was around to let him in and why doesn't Cap or Black Widow know about it? Well, some eagle eyed fans may have spotted the number 1983 next to the archive, but the coloring and distance makes that difficult to confirm. If it is 1983, then that could mean the archived video is from the year 1983.

If this video is showing that Ant-Man not only does escape the Quantum Realm, but also winds up in the past, then the Avengers would learn Ant-Man has already traveled through time. Potentially, Scott could be the one to bring this video to their attention in an effort to prove what he accomplished. Not only does this then explain Cap and Black Widow's responses, but also shows them a potential path to victory against Thanos.

Black Widow and Captain America in Avengers Endgame

Captain America's Winter Soldier Suit

Even if the Avengers missed meeting back up with Ant-Man initially, that reunion will happen at some point. When it does, he will be sure to explain what happened to him and his experiences. And based on everything else we know about Avengers: Endgame, it appears they will latch on to the idea of time travel. The popular theory suggests the Avengers will travel throughout time in an effort to prevent the snap from happening, possibly by making sure Thanos never gets his hands on the Infinity Stones to begin with. But, traveling through time can get complicated, as doing the wrong thing or looking the wrong way could alter the course of history beyond what the Avengers are trying to do.

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This is why the shot of Captain America suited back up in his stealth suit from Captain America: The Winter Soldier also appears to be a hint towards the film's time travel plot. The costume is not what Cap has been shown wearing in official promo art for the movie, so what reason would he have for wearing a stealth suit other than having to relive the events of his second solo movie? Set photos previously showed Tony Stark undercover in S.H.I.E.L.D. gear, possibly to try and conceal his identity and reduce the impact of his presence as he alters a point in time. It isn't clear why Steve would need to go back to 2014, but this would appear to be what he is doing.

The Avengers: Endgame's Title Reversed Dusting Effect

Avengers Endgame title

The final and arguably most clever sign of Avengers: Endgame's time travel plot isn't with any of the actual footage from the movie. Instead, it comes in the title and logo reveal sequence near the end of the trailer. The camera zooms out from a broken Avengers "A" before revealing Endgame is the title. But, it's the way that the logo is being reformed that could be another great clue to what the movie will hold.

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The Avengers team is obviously broken and scattered, but they will come to fight on the same side for the first time since Avengers: Age of Ultron in this movie. The reforming of the "A" could be symbolic of the Avengers team coming back together, but it also looks exactly like the effect that reversing time can have on an object. Both Doctor Strange and Thanos have demonstrated how the Time Stone can reverse time and piece back together something that was broken. For Doctor Strange, it was with repairing Hong Kong at the end of his solo movie, while Thanos uses this ability to bring Vision and the Mind Stone back to their regular state in Avengers: Infinity War, only so he could preserve the stone by ripping it out of the android's head himself.

Avengers: Endgame isn't going to completely reverse the events of the MCU in this literal of a fashion, but the heroes will definitely attempt to reverse the outcome of the Battle of Wakanda. It remains to be seen whether that means more sacrifices have to be made in the fourth film, but the goal will be to undo the snap, reverse the dustings (which is officially known as The Decimation), and bring several major MCU characters back to life. This logo effect doesn't appear to just be a stylish reveal, but actually further plants seeds for what is to come.

Since this is just the first trailer for Avengers: Endgame, Marvel Studios was never going to show anything that blatantly revealed a time travel element. Marvel only released two trailers for Infinity War, so there's not even a guarantee that a second trailer for Avengers 4 will confirm this element of the plot. They may, instead, decide to keep the marketing as vague as possible, only laying small clues like these for fans to discover. Most have accepted or believe time travel is coming in Avengers: Endgame, but it's finally nice to see some official evidence on the matter.

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