There are four Marvel movies hitting theaters in 2014, and the first of the group, Captain America: The Winter Soldier released its first full-length trailer last week, taking advantage of the Marvel movie buzz surrounding the press junket for Thor: The Dark World and its worldwide theatrical release beginning this week in the UK.

The third of the bunch, joining The Amazing Spider-Man 2 in theaters next May is X-Men: Days of Future Past, and its studio Twentieth Century Fox took advantage of last week’s buzz to let fans know that its first trailer was on the way as well. Fox kicked off its official marketing campaign with an Instagram teaser, a series of photos from cover stories in print magazines and a Twitter livechat with director Bryan Singer yesterday where he hinted at what was to come from the first Days of Future Past trailer.

With principal photography wrapping in August and lots of post-production special effects work still required, Singer explained during his Twitter Q&A that today’s first teaser trailer for the biggest X-Men team-up yet is focused squarely on the characters, much like the rough footage was that played at San Diego Comic-Con back in July. And of course, there are a lot of them.

As it turns out the trailer is nearly identical to the Comic-Con footage, featuring interesting shots in the past (1973) and future, the latter of which we see returning characters from the original X-Men trilogy with new, combat-appropriate costumes. The major change from the Days of Future Past comics is that instead of sending Kitty Pryde back in time, the movie will send film franchise poster boy Wolverine (Hugh Jackman) – or more specifically, his conscience – back in time to his younger, ’70s self to reunite Professor X, Magneto and other old school X-Men to prevent a certain event in the past from happening to save their future.

Singer revealed that about 70% of the film takes place in the past so it does serve more as a sequel to X-Men: First Class, and as for the new characters including Bishop, Sunspot, Warpath and Blink, who show up only in the future – They’re teased but are given no dialogue in the trailer. Some of these characters will have important roles to play since they’re the most likely to live on into sequels and spinoffs (see: X-Force).

X-Men: Days of Future Past is the first film in the long-running series to introduce time travel, a major plot device in Marvel Comics, and has the potential to redefine the franchise, correcting continuity errors of the past and laying the groundwork for the future. Does the trailer and its vastly different style and mood hold up against the action-packed first look at Captain America 2 and can its ambitious use of two casts and two time periods help Days of Future Past see big numbers at the box office?

Bryan Singer directs X-Men: Days of Future Past with newcomers Peter Dinklage, Omar Sy, Boo Boo Stewart, Fan Bingbing, Evan Peters, Adan Canto, Josh Helman, along with returning stars Jennifer Lawrence, Michael Fassbender, James McAvoy, Nicholas Hoult, Patrick Stewart, Ian McKellen, Hugh Jackman, Anna Paquin, Ellen Page, Shawn Ashmore, Halle Berry, Lucas Till, and Daniel Cudmore.

X-Men: Days of Future Past on May 23, 2014.

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