For now, all we know for sure is that series creators the Duffer Brothers have a four-season storyline worked out (so we’re halfway through now) – but there were a few clues scattered around season two to suggest what we might expect.

Starting with…

More Shadow Monster

This series of Stranger Things tied up a LOT more loose ends than the first, with the portal to the Upside Down now sealed off, Hawkins lab apparently closed for good and Jonathan and Nancy finally getting together (poor Steve).

However, the kids’ Snow Ball idyll was marred by the final shot of the series, which saw the devilish Smoke Monster that had been terrorising our heroes (aka the Mind Flayer) land on the roof of the school in the parallel Upside Down dimension, ready to get revenge for his defeat in the season finale.

“They’ve shut the door on the Mind Flayer, but not only is it still there in the Upside Down, it’s very much aware of the kids, and particularly Eleven,” Ross Duffer told The Hollywood Reporter.

“It had not encountered her and her powers until that final episode. Now, it knows that she’s out there. We wanted to end on a little bit of an ominous note.”

Looks like the battle is far from over…

Dustin and Hopper might be in trouble

Though most plot threads were neatly tied off by the end of Stranger Things 2, we couldn’t help but notice one part of the series that remained unresolved – what, exactly, was the deal with the spores sprayed in the faces of Dustin and Hopper?

At two different points in the series, both characters were sprayed full in the face with a mysterious substance while underground in the Upside Down vine tunnels, only to shrug off the disgusting attack and carry on with their plans.

Now, we can’t be the only ones to think that this set-up has to have some sort of pay-off in the next season, especially considering Will’s infection from Upside Down forces proved so explosive this series. And putting sunny Dustin and tough Hopper through the wringer next year would certainly be quite the shake-up…

Eleven’s sister will be back in action…

It seems very likely that we haven’t seen the last of Eleven’s “sister” Kali/Eight, with the superpowered illusionist escaping the police at the end of episode seven and apparently still keen on taking Eleven on a mission of vengeance against the men who wronged them.

In fact, given how abruptly her story ends, we wouldn’t be surprised if Kali and her Warriors-esque gang turned up in Hawkins to cause trouble in the next season – and with her mindbending powers, we’re betting she could cause a lot of damage.

And there might be some more superpowered siblings out there

So far, of all the kids experimented on in Hawkins lab we’ve been introduced to Eleven and Eight – so where are the others? Were some failed experiments who didn’t survive the testing, or are Nine, Ten and the others still out there somewhere, staying under the radar just like Eleven was?

If they are, how awful was the Hawkins lab security that literally every one of their test subjects was able to flee?

Will Dr Brenner return?

In the Kali/Eleven episode, it was hinted that sadistic scientist Dr Brenner (Matthew Modine) might actually still be alive, after apparently expiring offscreen at the hands of the Demogorgon in season one.

“I would say that if we were going to kill Brenner… as an audience member watching the show, if that was his death, that would be very unsatisfying to me,” Matt Duffer told IGN.

“When the monster jumps on him and we cut away. He would deserve much more than that as an ending. So yes, there’s a possibility of seeing him again.”

Of course, it could be that the ex-Hawkins Lab worker Eleven and Kali were intimidating would have said anything to save his own skin and the Duffers are just playing with us, but we’re betting this isn’t the last we’ve heard from Eleven’s errant ‘Papa’.

The Steve/Jonathan/Nancy love triangle continues

At the end of season one, we totally wanted Nancy and Jonathan to get together – but after seeing Steve’s heroism, babysitting nous and regret over losing Nancy, we’ve flipped right round again and are totally Team Steve.

And after the longing look Steve gives Nancy while dropping off Dustin at the Snow Ball in the season finale, we’re betting he’s not quite done with the love triangle either (unless he just leaves to go to college in the next season and we never see him again).

Will might actually get some time off

After two season of suffering, being covered in alien goop and screaming in fields, it seems that Will Byers (Noah Schnapp) might finally get a rest from trauma in Stranger Things 3 – at least according to one of the series’ creators.

"I feel like we really put Will through the wringer," Matt Duffer told THR, "and maybe now we're going to give him a break at least."

However, Schnapp wasn’t quite so sure that Will’s out of the Mirkwoods yet…

"I personally think it's not all out of him," he said. "I feel like it can't be.

“There's this massive monster taking over all of Hawkins, and all you have to do is light a few fires and turn on a few heaters, and he's gone? It just doesn't make sense to me, really. He's still there — I just don't know how."

And finally… we might have to wait a while until we see everyone again

After Stranger Things season one’s release it took around 15 months for the Duffers to write, film and edit season two, and rumour has it that fans could have just as long (if not longer) before season three hits Netflix – after all, the writing team have apparently only just began work on the next episodes, and even if it takes the same amount of time that would push the series into early 2019.

Furthermore, the Duffers plan to carry on the story in tune with this time-gap, ageing up the characters and progressing their maturation in more-or-less real time.

"They're going to be almost a year older by the time we start shooting Season 3," Matt Duffer told THR. "It forces the show to evolve and change, because the kids are changing."

Still, however long we all have to wait we’re sure fans will be chomping at the bit for more Stranger Things when it does finally arrive – and at least it’ll give us plenty of time to binge the whole thing over again a few times.

Stranger Things 2 is streaming on Netflix now