Marvel Studios just showed a huge chunk of footage from Avengers: Infinity War at the D23 Expo and there almost aren’t words for it. But we’re going to try.
The footage began with probably a two-minute intro of footage from the first several movies, all focusing on the Infinity Stones we’ve seen so far. Then, the Marvel Studios logo, and on to the new stuff.
The Guardians of the Galaxy are flying around. “Put on your mean faces,” Star-Lord says, because he expects something nasty. There has been crazy destruction, and then a body smashes up against their ship. “Get it away,” Rocket says. They bring the body in and it’s Thor. (Spoilers for Ragnarok, we guess?) Mantis wakes him up and Thor jumps up and exclaims “Who the hell are you guys?”
Next we see the Guardians with Thor, flying to another planet, and when they arrive—again, it’s just massive destruction again. They all know something is very wrong.
Cut to Earth. Scarlet Witch is moving around some cars or something and a female voiceover says “Death follows him like a shadow.” Loki emerges and presents the Tesseract to someone who is taller than him.
Cut to Queens and the hairs on the arm of a young Peter Parker stand up on end. He turns around in fear and we see a ship flying toward a planet we assume is Earth. “We have one advantage,” Tony Stark says. “He’s coming to us.” As the ship crashes, we see Mantis, Iron Man, Star-Lord, Doctor Strange, and a few others characters in total shock.
Fun really isn’t something one considers when balancing the universe,” a voice says. Gamora turns around in total horror. “But this puts a smile on my face.” Star-Lord: “Oh no.” And out of a black hole emerges the purple madman, Thanos.
A fight begins. Doctor Strange is putting down platforms and Star-Lord is jumping off them, shooting his guns. Cut to Spider-Man, in his new suit revealed at the end of Homecoming, jumping through the air. A shot of Vision behind bars. A shot of a Wakandan army which includes Bucky. Captain America comes out of shadows with a full beard. Black Widow is shown with blonde hair. Iron Man has new, very sleek armor. Someone is using the Hulkbuster armor. Just a huge montage of shots.
Peter Parker is on the ground very hurt. “I’m sorry Tony,” he says behind tears with Iron Man holding his head. Thanos grabs Thor’s head and squeezes. Then Thanos, in the heat of battle with the Infinity Gauntlet on his hand, uses the power of the two stones he has (Purple and Blue, I think) to grab a moon. He starts to drag it toward whatever planet everyone is standing on. The debris starts to fly and... cut to title card.

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