Avengers: Endgame is now in theaters, where it's crushing box office records--it's already the second biggest movie ever, with the potential to top Avatar. That it's managed to do so well is not a big surprise; last year's Infinity War was one of the biggest movies ever, and Endgame explicitly ties up the lingering storylines from that movie and those from the first 10 years of Marvel films.
The trailer above provides yet another look at what to expect from this concluding chapter of the Infinity Saga, as the remaining heroes try to deal with Thanos and the fallout from Infinity War. The movie will be followed by Spider-Man: Far From Home, which has also now gotten a new trailer--but it's one you'll want to skip until you've seen Endgame. Although Endgame is, as noted above, the end for many storylines, it's actually Far From Home that marks the conclusion of the Marvel Cinematic Universe's Phase 3. Phase 4 will kick off with whatever comes after that, although Marvel has not yet confirmed just what that will be.