The Guardians of the Galaxy will meet the Avengers in Infinity War 

The Guardians of the Galaxy will battle alongside Iron Man, Captain America, and the rest of “Earth’s mightiest heroes” in

Fans, go ahead and take a breath for a moment. … You good? Okay, onward.

That means, as the concept art above shows, we’ll see Rocket Raccoon blasting away beside Thor the thunder god.

The news came via a behind-the-scenes video feature showing Robert Downey Jr., new webslinger Tom Holland, and Star-Lord (you’ve heard of him, right?) Chris Pratt on their first day at Pinewood Studios in Atlanta, standing on a set that looks like a blasted wasteland (surrounded by a massive green screen.)

Before that, the two also popped up in a Facebook Live event in which Downey took fan questions from the set. During the nearly six-minute livestream, below, fans got a glimpse of Holland, whose face was covered in black dots used for CGI recognition, as he posed as Downey’s own personal cameraman, and Pratt, who dropped by to let Downey know they were ready to shoot.

will actually be two movies shot back to back, essentially

, and Marvel Studios president Kevin Feige says it’s the culmination of the story they started telling back with 2008’s original

, set for release May 4, 2018, then the as-yet-untitled follow-up on May 3, 2019.

Both movies are being directed by Joe and Anthony Russo, who made the Captain America films

Things in the Marvel Cinematic Universe are a mess after last year’s clash of heroes in

. Iron Man and Captain America are still holding grudges. “Tony is not talking to Steve… The Avengers are basically a name with nobody in it,” says Christopher Markus, who co-wrote the screenplay with Stephen McFeely. “The world is vulnerable.”

Stepping up to the plate to take a swing at that world: galactic death-god Thanos (Josh Brolin), who has been trying to amass infinity stones (the gems that power The Vision, and allow Doctor Strange to bend time, among others) for a gauntlet that will give him dominion over space, time, and all reality.

Surprise — he’s not going to use it to make the universe great again.

“We know they’re going to face Thanos. We’ve been setting that up since

1,” says Feige. “How do you do that in a way that’s unexpected, that pits the Avengers against somebody who is more powerful than anybody they’ve ever faced, and yet make them completely unprepared to face them? Well, tear them apart. Which is why we made

Even without his team, Tony Stark is trying to hold the fort. The video shows concept art of him standing before a line of Iron Man-like sentinel droids, similar to the ones he deployed (with disastrous results) in

“Tony senses this greater threat approaching, so he is doing everything in his power to keep the Earth safe,” says Joe Russo.

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