Not one, not two but FIFTEEN Avengers and Guardians of the Galaxy actors just united to reveal the FIRST trailer for Avengers: Infinity War.

Assembling on stage at Disney fan event D23 in California, the cast revealed an action-tastic FIRST trailer for the huge next Avengers movie. The massive crossover film will see the Guardians and Avengers unite in an earth-and-space stretching battle to take down Thanos, who is trying to collect all of the Infinity Stones and inflict his will on ALL OF HUMANITY.

The first trailer for the movie was shown exclusively to fans at D23, in the A-list company of Robert Downey Jr. (Iron Man), Chris Hemsworth (Thor), Mark Ruffalo (Hulk), Tom Holland (Spider-Man), Josh Brolin (Thanos), Benedict Cumberbatch (Doctor Strange), Chadwick Boseman (Blank Panther), Paul Bettany (Vision), Elizabeth Olsen (Scarlett Witch), Don Cheadle (War Machine), Sebastian Stan (the Winter Soldier), Anthony Mackie (Falcon), Pom Klementieff (Mantis), Karen Gillan (Nebula), and Dave Bautista (Drax).

In it, we see some of our fave Marvel Cinematic Universe heroes come together for the first time: including Thor meeting the Guardians of the Galaxy.

The trailer, which is yet to be released publicly, shows the Guardians are cruising through space in their ship, something – or rather, someone – hits their windscreen. They bring in the offending body and you’ve guessed it! It’s Thor.

Mantis wakes Thor using her powers – much to the horror of a VERY freaked out Thor.

It’s enough to give us a taste of what to expect when the Guardians and Avengers worlds collide when the movie hits cinemas in May 2018, but we'll have to wait a little longer for the trailer to hit the internet.

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