IGN has an exclusive trailer breakdown with the Duffer brother.
Interesting new things they reveal:
The biggest challenge that the characters face is that they're so spread out now.
They call this their "Game of Thrones Season" because of how spread out everyone is.
The new baddie is named Vecna, and they compare him to Freddy Krueger, Pinhead, and Pennywise, and that they've wanted to do this kind of bad guy for a while now.
A big part of the season is going to focus on the characters dealing with their trauma from the other seasons.
The scene with Max talking to Billy's grave is from Episode 4, which is titled.... "Dear Billy". They say several times that Max is going to be a big part of the season.
The clock is an important part of the story this season, and seeing it is bad.
The flying monsters are Demobats, and one isn't to dangerous, but when you get a lot of them together they can be.
The Russia scenes were filmed in Lithuania, with a few interiors filmed in Atlanta.
Joyce is now working as a telemarketer, and the package with all of the Russian stamps sets her off on an "epic journey".
Another big part of the season will be the characters moving on to high school, with some of them getting involved in things like sports and finding new friends.
We'll also see Eleven struggling to fit in with normal kids at school, and trying to figure out who she is without her powers.
The fight we see with the Demogorgon is something they've wanting to do for a while, and takes place it happens is called the Demopit.
The scene with her in the bloody hospital gown takes place before Season 1, and will be the earliest stuff we've seen with her. It sounds like it will be dealing with what happened to the other numbers.
We'll be spending the most time in the Upside Down on any season so far.
The guy with no eyes is Victor Creel, who is played by Freddy Krueger himself, Robert England, and he plays a pivotal role in the season. They don't say anything about it, but I'm assuming it's not a coincidence that his last name is Creel, and we'll be visiting the Creel House.
Vecna is 90% practical, and the makeup for him was created by the same guy who did The Night King for Game of Thrones, and the radiation makeup for Chernobyl.