Warning: Contains spoilers for Stranger ThingsSeason 1.

LONDON -- It's only been around six weeks since Stranger Thingsexploded its way onto our Netflix accounts, and excitement for Season 2 -- which was officially confirmed for 2017 Wednesday -- has reached fever pitch.

The Internet has been chock-full of theories and questions about where the Duffer Brothers' story might be heading, and the launch of a new teaser trailer -- which dropped on the official Stranger ThingsTwitter account on Wednesday morning and features what we can assume are the nine Season 2 episode titles -- has kicked the discussion into overdrive.

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From Eleven's whereabouts to Will Byers' ongoing misery, we've rounded up some of the biggest questions Season 2 needs to answer...

1. What exactly is happening to Will Byers?

Will Byers basically spent the entirety of Season 1 slowly dying in an alternate dimension. Despite his eventual rescue, though, things don't look like they'll be getting better for him anytime soon. It was clear from the final scene of the Season 1 finale that Byers has been infected in some way by that Alien-like creature Hopper tugged out of his mouth in the Upside Down; the question is, what exactly is wrong with him?

Has his experience in the Upside Down turned him into a kind of walking portal between the two dimensions? Is some remnant of the creature that first kidnapped him lurking in his stomach? Has he been inhabited by some kind of infection that he risks spreading to the other citizens of Hawkins? Or maybe it's all of the above?

Whatever it is, things don't look good.

2. What was the deal Hopper made with Dr Brenner?

The obvious implication in the Season 1 finale is that Hopper has fed Dr Brenner information about Eleven's whereabouts in exchange for being allowed to go after Will.

"You've gotta give me your word... nobody's ever going to find out about this," says Hopper, puffing on a cigarette and looking a bit troubled. "And those other three kids -- those boys -- you're gonna leave them alone... then I'll tell you... tell you where your little science experiment is."

So that's all pretty straightforward, right? Well, maybe not. We don't know exactlywhat Hopper tells Brenner because we don't see the whole exchange, and overall the whole sequence feels a bit off (would Hopper, who seems like a pretty decent guy, really give up Eleven just like that?); there's also that mysterious sequence near the end of the finale, when Hopper -- still smoking and looking just as troubled as always -- gets into that ominous black car with what looks like another government official.

What does that serious, resigned expression on his face mean? Is he now colluding with Brenner's organisation? Has he still got part of the deal he made left to fulfill? Or did he pull some kind of trick on them which he knows he'll shortly be paying the price for?

Then there's the small matter of this next question...

3. Why is Hopper leaving food in the woods?

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Just to make the whole Hopper storyline that little bit more mysterious, the last time we see him he's out in the woods on Christmas eve, leaving some supplies in a box among the trees.

The final thing he puts in is some Cellophane-wrapped waffles (ie. Eleven's favourite food). After he closes the box he looks up, stares off into the distance as Christmas music plays in the background, and gives a small smile.

It seems like there are only really two possibilities here: either Hopper knows Eleven is still alive and he's leaving her food on the sly, or he's hopingshe's still out there somewhere and he's leaving her supplies just in case (possibly in an attempt to assuage some of the guilt he feels for giving her up).

All of which leads us nicely on to the next big question...

4. Is Eleven still alive?

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"We don't know about Eleven," Ross Duffer told Entertainment Weeklyin a recent interview. "We leave that up in the air."

Just the fact that the Duffer Brothers haven't ruled out the possibility of her return is a good sign, though.

The main thing to remember is that we don't see her die in the finale -- the black dust that the monster disintegrates into engulfs her and hides her from view, and when it's cleared she's nowhere to be seen.

One possibility is that her efforts to tear apart the monster were so great they destroyed her; the more likely possibility (at least in our opinion) is that she destroyed the monster but somehow got pulled through into the Upside Down in the process. It could just be our wishful thinking, but if you look closely at the screengrab above it sort of looks like a miniature portal is opening in the place where the monster was pinned to the wall.

Also, Millie Bobby Brown (who plays Eleven) shared an excitable Instagram post when the Season 2 announcement was made on Wednesday morning, and that's hardly the kind of thing you do if you're not even going to be in the show anymore, right?

Right?

5. Was the monster really killed?

If our hopes are confirmed and Eleven is still alive, though, does that mean the monster could still be out there somewhere, too?

This one seems less likely -- we can't imagine the Duffer Brothers re-using the same antagonist in Season 2 -- but there's always the chance plant man might have some friends. Or some offspring...

6. How will "MadMax" feature in the Season 2 opener?

One of the interesting things about the Season 2 teaser was that it appeared to show all the titles for the nine episodes that are set to feature. The first of these -- and the subject of a fair bit of discussion over on Reddit -- is "MadMax".

Could the reference to the popular post-apocalyptic action film hint at some kind of apocalyptic beginning to Season 2?

"I will say the opening scene [of the premiere] does not take place in Hawkins"," Matt Duffer told EW.

Intriguing. Then again, it's also very possible that "MadMax" refers simply to the original 1979 film, and that it will somehow be referenced by the characters in the opening episode.

7. What does "The Pollywog" refer to?

The title of episode six -- "The Pollywog" -- sounds a bit ominous to us. If we had to guess, we'd say it's probably a reference to the tadpole/slug-like creature Byers croaks into the sink in the Season 1 finale.

Maybe the slug gets into the water supply of Hawkins and starts wreaking havoc? Maybe it grows into something larger?

Either way, we're willing to bet it's not going to be pretty.

8. Who is "The Lost Brother"?

Another intriguing episode title is the potential Season 2 finale episode, "The Lost Brother". From the sounds of it, Season 2 will either revolve around -- or at least end with -- yet another disappearance.

Jonathan Byers and Mike Wheeler, both of whom are brothers, are two possibilities. Then again, who knows? The lost brother could be someone we've yet to meet.

9. How many new characters will we see?

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Well, we'll definitely be getting some. According to that EWinterview, there are going to be at least four (presumably quite big) characters joining the original cast in the show's second season.

Seeing as Hawkins isn't going to be the only setting, maybe we'll see some characters from neighbouring towns come into play (or maybe towns further afield that have their own portals into the Upside Down).

10. What other secrets does the Upside Down hold?

It sounds like we'll be getting a lot more of the Upside Down in Season 2 (Season 1 really only scratched the surface, after all).

"“We obviously have this gate to another dimension, which is still very much open in the town of Hawkins," Ross Duffer told EW. "And a lot of questions there in terms of, if the Monster is dead, was it a singular monster? What else could be out there?

"We really don’t go in there much until they go in to find Will at the end. So we’ve opened up this doorway, and to us it’s exciting to talk about, like, what else is behind there? There’s a lot more mystery there to be solved.”