The Stranger Things season 3 finale had us all asking questions.

At the end of the episode, we saw the Byers family pack up and move out of Hawkins (can you blame them?), along with Eleven, who Joyce took in following Hopper's heartbreaking death. But, just as we thought that it was going to end and we were wiping our tears away (because how emotional was that last episode?), bam, they played a scene during the credits that completely threw a spanner in the works and left the internet with even more queries.

At the very end of the final episode, we were transported to Russia.

The post-credit scene showed what appeared to be a Russian-prison or secret base where the Soviets had somehow gotten their hands on a Demogorgon and were sending it onto one of the prisoners, presumably as some sort of punishment, torture method, or maybe even as part of some twisted research. Who knows?

It left us reeling for more.

First off, what happened to Eleven's powers? Why did they disappear? Also, how on Earth did the Russians get hold of the Demogorgon? And who is the "American" that the guards refer to in one of the locked cells? So many unanswered questions. We need Season 4, right now.

All of the "hows" and "whys" naturally sparked a ton of fan theories about what will happen next.

Superfans put on their detective hats and attempted to suss out the answers to all of their burning questions.

A popular one is that Eleven will never get her powers back.

But we're not convinced. Despite losing her abilities at the end of the finale, we put it down to sheer exhaustion after saving the world, again.

And there's the Chernobyl theory...

One Reddit user has been making some wild predictions for Stranger Things season 4, theorizing that the Chernobyl nuclear disaster could be at the center of the show's next season. Sound crazy?

The recent HBO drama has done very well...

The series reenacts the tragic events of the nuclear catastrophe and has since received rave reviews from both fans and critics alike.

But how does it tie into Stranger Things?

Well, a fan posted his theory to Reddit, in a post titled, "I figured out season 4 and I hate myself for it." The fan starts off by noting that each of the Stranger Things installments has taken place over an entire season - the first was set in winter 1983‬ around Christmas time, Season 2 took place in fall 1984‬ around the time of Halloween, and finally, Season 3 was set in summer 1985‬ over the Independence Day festivities. This, therefore, puts Season 4 as being set in Spring 1986 ‬to coincide with the Easter holidays and will likely span into spring break, the same time as the Chernobyl disaster.

The user was also quick to point out that post-credit scene.

With the clip taking place in Russia, the fan adds that "Doctor Owens said that they use something familiar to convince the public to not look any further into the strange happenings." Therefore, the fan suggests that big battle for Eleven may be on the cards, either with the Russians and "upside-down" monsters causing the disaster – or, alternatively, the explosion could be to keep the showdown a secret from the public.

During season 3, we'd already started to see the show extend to Russia.

During the latest season, we were introduced to Russian spies who were operating in a secret facility under the mall, who appear to be attempting to open up the gate to the "Upside Down" which Eleven closed in the finale of season 2. In fact, co-creator, Ross Duffer, recently hinted that season 4 may go for "plotlines into areas outside of Hawkins," which could well mean Russia. So, it doesn't come as too much of a shock that the post-credit scene takes place in the region.

And many people have pointed out the resemblance between Stranger Things and HBO's Chernobyl.

So much so, that people took to Twitter to write bout how much the new season of Stranger Things reminded them of the HBO drama surrounding the nuclear accident.

The dates for Chernobyl might match up, but it does seem like a bit of a stretch.

After all, something just doesn't feel quite right about the Netflix show incorporating a devasting nuclear disaster into its plotline.

And it seems that the internet hasn't taken the fan's prediction very well either.

Digital Spy said that the theory "may be the worst we've ever read," while Vice said that "referencing New Coke and Ghostbusters or whatever is one thing; creating a far-fetched, fictionalized story to explain a catastrophic disaster is another."

Although some people on Twitter actually like the sound of the theory.

However bold, weird, or distasteful the theory may appear, it seems like some fans wouldn't be opposed to the crossover.

Although others didn't agree.

Turning the horrific nuclear disaster into some kind of sci-fi battle scene face-off kind of feels like the scale of the incident is being trivialized, and for what? Either way, there's been no indication that this theory is true, so all we can do is sit tight and wait until Season 4 to find out.

Which shouldn't be too long...

It's the news that we've all been waiting for. A new listing from Production Weekly indicates that Netflix is gearing up to begin filming the fourth season already.

Filming will apparently be starting very soon.

Reports say that Stranger Things 4 will start shooting in October this year.

Which means that the newest season will premier...

As soon as 2020!

Here's the confirmation we were waiting for.

Strangers Things' official Twitter account dropped this surprise trailer. If you can't wait until its release here are some films to keep your Stranger Things addiction fulfilled.