The first trailer for Avengers 4 - officially called Avengers: Endgame - has arrived.
It marks the 10 year anniversary of the Avengers movies - from Tony Stark's first outing as Iron Man to the devastating battle against Thanos in Avengers: Infinity War, which was released earlier this year.
The trailer shows many of Earth's heroes still dealing with the loss of their closest friends who faded into dust at the end of Infinity War.
But what else can we expect from the movie? Directors and brothers, Anthony and Joseph Russo, are being very quiet about what will happen in the new film, which is due out in April 2019.
But we've had a look about and here are some ideas of what to expect. Watch out though, there are SPOILERS AHEAD!
At the end of the last film, we saw many of our beloved heroes disappear as villain, Thanos, completed his mission.
For many of us it was a very sudden goodbye.
But many think that this won't be the last we see of the A-team.
The cast list shows that all the main players will be returning - including Benedict Cumberbatch as Dr Strange, Tom Holland as Spider-Man, Zoe Saldana as Gamora and Tom Hiddleston as Loki.
We can't be sure that their characters have reappeared - it could be that they are part of flashbacks in the film - but the fact that so many of the actors will be appearing in the next film makes us hopeful!
You may remember that Steve Rogers, Captain America, was one of the Avengers that survived the last film.
However, this might be the last time we see the formerly-frozen soldier in his superhero suit.
The actor who plays him, Chris Evans, has said it's time to give up the shield and move on to other projects.
So what could this mean for his storyline in Avengers 4? We'll have to wait and see!
Oscar-winning actress, Brie Larson, is joining the line up in this film - playing superhero Captain Marvel.
Captain Marvel has the powers of super strength and flight - that's quite a combination.
And if you like two-for-one deals, you'll be pleased to know that the trailer for the new Captain Marvel film will also be dropping this week!
This is more superhero news than we can handle!
It's fair to say that the Avengers has an overwhelmingly large cast - it packs in more cameos and stars than any other superhero franchise.
But there is another character to add to the line up!
Katherine Langford, best known for her appearances in 13 Reasons Why and Love, Simon will be joining the star-studded cast. However, we're in the dark as to what her role will be.
Some believe she might play Cassie Lang, the daughter of Ant-Man. Others are thinking she might be Kate Bishop, a potential Hawkeye replacement, after the original Hawkeye, Clint Barton, mysteriously did not appear in Infinity Wars.
We know that Jeremy Renner - who plays Clint Barton - will be appearing in Avengers 4, however. So how will these storylines tie together?
A more surprising theory, is that some think that she might be there not as an Avenger, but as a villain! Possibly one to rival Thanos himself.
A leaked photo from the set of the Avengers shows actress Gwyneth Paltrow, who plays Tony Stark's wife - Pepper Potts, in a new kind of outfit all together.
Wearing a purple suit very similar to Iron Man's super robotic suits, she looked like she could fit right in with the Avengers crew.
Some think that this will be Pepper's turn to shine, after the character has often been side-lined to smaller stories.
What are your theories for the new Avengers film? Let us know in the comments below!