They are heading into space to find Thanos, presumably, but look closer at who's with them.
Thor (Chris Hemsworth) says at the end of the trailer, pointing to their newfound ally: "I like this one".
Thor returns, but there's a grim feel to the new Avengers: Endgame trailer.
But now Tony is back on Earth, striding purposefully through the Avengers compound, with the remaining Avengers... and Karen Gillan's Nebula, who was also left behind on Titan. We see a thin, weak Steve Rogers from "Captain America: The First Avenger".
Avengers: Endgame will presumably follow our heroes as they attempt to undo the decimation caused by Thanos and bring back their fallen comrades, including Spider-Man.
Along with the official poster, Disney/Marvel released the first full trailer to Avengers: Endgame, which hits theaters April 26. In the next black and white scene, Captain America is carrying a flag-draped casket with only the red stripes of the flag in color.
Here's what we learned from the new trailer - and just a warning that this obviously contains spoilers for Avengers: Infinity War. You can get a refresher by watching the trailer below. Aside from the natural passage of time, we may see Avengers characters jumping into different timelines in their attempts to destroy Thanos (Josh Brolin).