“Don’t forget this might be dangerous, so let’s put on our mean faces,” cautions Chris Pratt’s Star-Lord, guiding the Guardians of the Galaxy’s ship through deep space.

That’s how the action begins in the first trailer to Avengers: Infinity War, which first premiered a week ago for fans at Disney’s D23 Expo and then played again Saturday night at San Diego Comic-Con. Marvel superfans who weren’t able to make the trip to either of the conventions have been clamoring for leaked footage of the trailer to Anthony and Joe Russo’s (The Winter Soldier, Civil War) superhero team-up, which is scheduled to hit theaters May 4, 2018.

Infinity War is set four years after the events of Guardians of the Galaxy Vol. 2, and sees the Avengers and the Guardians link up to try and stop Thanos (Josh Brolin), who is hell-bent on collecting all the Infinity Stones and controlling the galaxy. The film will not only feature all the Avengers and Guardians, but also Tom Holland’s Spider-Man, Tom Hiddleston’s Loki, Benedict Cumberbatch’s Dr. Strange, Chadwick Boseman’s Black Panther, Paul Rudd’s Ant-Man, and, of course, Samuel L. Jackson’s Nick Fury, to name most.

But back to that trailer. The Guardians’ ship is floating through a particularly scary-looking section of space when all of a sudden—splat!—Thor (Chris Hemsworth) hits their windshield, sporting his short hair and gladiator treads from Thor: Ragnarok. The Guardians bring him inside their vessel, and Thor takes one look at Star-Lord and asks, “Who the hell are you guys?”

And that’s just the beginning. You can watch a leaked version of the trailer right here while you can.

Update 8/9/17: The trailer can now be found on YouTube, for now.