It was around this time last year that Marvel Studios released the first official teaser trailer for Avengers: Age of Ultron which opened in theaters the following May. This is why fans are eagerly anticipating the first trailer for Captain America: Civil War (which has the same release window in 2016) - but as we learned this week, Disney is holding off and attaching it to Star Wars: Episode VII - The Force Awakens when it opens mid-December.

So, all we have to go on are unofficial set photos and leaked promo art, which have been quite revealing when it comes to determining which characters are on which side of the Civil War conflict - an event that arises out of a need to register and hold superheroes accountable. But of course, there will be twists and turns so what we see may not be what it seems.

We're going to delve into rumors and spoilers so if you wish to avoid knowing character and plot details for Captain America: Civil War, stop reading here. You have been warned.

Captain America: Civil War Teams

Before we get into what characters may be switching sides, here are the team breakdowns:

Team Cap/Anti-Registration

  • Steve Rogers / Captain America
  • Bucky Barnes / The Winter Soldier
  • Clint Barton / Hawkeye
  • Sam Wilson / Falcon
  • Sharon Carter / Agent 13
  • Scott Lang / Ant-Man
  • Wanda Maximoff / Scarlet Witch

Team Iron Man/Pro-Registration

  • Tony Stark / Iron Man
  • James Rhodes / War Machine
  • Natasha Romanoff / Black Widow
  • Peter Parker / Spider-Man
  • T'Challa / Black Panther
  • Vision

Outside of Scarlet Witch, who actress Elizabeth Olsen claims will have a "huge transformation" of powers, Cap's team is relatively under-powered. This is where the latest rumor comes into play. We've heard speculation that Black Widow may just be working undercover and is actually loyal to Cap but that seems too obvious and Tony Stark isn't that dumb. And of course, if the film is drawing inspiration from the comics, Black Panther and Spider-Man are probably not truly pro-registration, but the twist may come from Vision - Earth's walking, talking Infinity Stone.

Vision Avengers: Age of Ultron Textless Poster
Paul Bettany as Vision

The rumor comes from That Hashtag Show who claim that Vision will actually turn against Tony Stark in Captain America: Civil War. We should note this is the same source who claimed to have insiders revealing to them that Matthew McConaughey was in talks to play Norman Osborn in the MCU and we know he was offered (and turned down) the villain role in Guardians of the Galaxy Vol. 2. They do claim however, that this Civil War scoop comes from the same source as their info on Avengers: Age of Ultron which correctly explained the origins of Vision and connection to the Mind Stone.

More: Infinity Stones In Marvel Movies: What They Are & Where They Are

Their report continues to explain that Vision and Scarlet Witch do share a relationship in Captain America: Civil War but after "major events" Vision actually leaves Earth. This seems comparable to the Avengers 2 ending which sees Hulk bolting off (initially rumored to be leaving Earth as well) but Vision leaving Earth has major implications of Phase 3 of the Marvel Cinematic Universe. If true, this means Captain America 3 is already beginning to lay the groundwork for bridging the gap between Earth and the Marvel cosmic side - an inevitable happening leading up to Avengers: Infinity War.

Next Page: Vision's Role in the Marvel Cinematic Universe

Adam Warlock with Infinity Gauntlet in Marvel comics

Vision could potentially serve as the MCU's Adam Warlock, a character in the books with an Infinity Stone in his head, who's integral to the Infinity War storyline and battling the franchise's big bad villain Thanos (Josh Brolin). That would ultimately be a letdown to Marvel Comics readers who are still hoping to see Adam Warlock appear in the Guardians of the Galaxy movies, but it does keep the larger narrative simpler for Marvel.

This would mean moviegoers might be seeing Vision return in Guardians of the Galaxy Vol. 2 - where we suspect Thanos will reappear and more Infinity Stone lore will be explored. He could also be involved in Thor: Ragnarok which we already know features Bruce Banner a.k.a. Hulk as a lead character. After all, in Avengers: Age of Ultron, Thor's vision saw the realm of Asgard falling apart and the Mind Stone at the center of it.

Removing Vision from the field solves one problem of having an overly powerful quasi-cosmic character involved in Earthly matters. It also frees up Scarlet Witch - who has a romantic relationship with Vision in the comics - to pursue a more magical venture, perhaps even teaming up or training with Doctor Strange (Benedict Cumberbatch) down the road. The MCU seems to be leaning towards more "event" style movies and team-ups so this fits the bill. Seeing Vision in space is an exciting prospect and an idea that Guardians of the Galaxy 1 & 2 writer-director James Gunn has teased for a while; that an Avenger could meet-up with the Guardians. Perhaps that's Vision's destiny.

Next: Guardians of the Galaxy 3 & Other Marvel Phase 4 Musts

The movie stars Chris Evans, Robert Downey Jr., Scarlett Johansson, Sebastian Stan, Anthony Mackie, Emily VanCamp, Don Cheadle, Jeremy Renner, Chadwick Boseman, Paul Bettany, Elizabeth Olsen, Paul Rudd, Frank Grillo, Tom Holland, with William Hurt and Daniel Brühl. Marvel’s “Captain America: Civil War” is directed by Anthony & Joe Russo and produced by Kevin Feige. Louis D’Esposito, Alan Fine, Victoria Alonso, Patricia Whitcher, Nate Moore and Stan Lee serve as executive producers and the screenplay is by Christopher Markus & Stephen McFeely.

Captain America: Civil War will release on May 6, 2016, followed by Doctor Strange - November 4, 2016; Guardians of the Galaxy 2 - May 5, 2017; Spider-Man - July 28, 2017; Thor: Ragnarok - November 3, 2017; Black Panther - February 16, 2018; The Avengers: Infinity War Part 1 - May 4, 2018; Ant-Man and the Wasp - July 6, 2018; Captain Marvel - March 8, 2019; The Avengers: Infinity War Part 2 – May 3, 2019; Inhumans – July 12, 2019; and as-yet untitled Marvel movies on May 1, July 10 and November 6, 2020.

Source: That Hashtag Show