Everything you need to know about series two of Stranger Things

Netflix has shared a new teaser, poster and premiere date for the second season of Stranger Things - so it's time to go back into the Upside Down.

In October, fans will return to the town of Hawkins for a new chapter in the 80s-themed horror drama.

The first season made stars of its young cast and was a welcome return to TV screens for Hollywood actress Winona Ryder.

And season two promises to be even bigger and better.

Here is the teaser.

But there's more. Here's what we know about season two so far.

Don't worry, Eleven is back

Millie Bobby Brown's character went missing at the end of series one

Series one ended with Eleven (Millie Bobby Brown) being drawn into The Upside Down after defeating the show's monstrous Demogorgon villain.

But fans don't need to worry - her return was confirmed in February, when she was seen in the first teaser for the show.

Although it doesn't look like she's in a very good place...

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There are new characters joining the drama

The Stranger Things cast (both young and older) were partly responsible for the love shown to the show's first season.

And it's getting even bigger for the second.

Sadie Sink (right) plays Max, a new ally for the young characters in Hawkins

There will be a new addition to the younger cast in tomboy Max, who becomes friends with lead characters Mike, Lucas, Dustin and Will.

Max has an older brother Billy, who also joins the show, along with a boyfriend for Joyce Byers (Winona Ryder), a new government official trying to clean up what happened in Hawkins along with a number of other adult characters drawn to the town after the events of series one.

Sorry, but Barb is definitely dead

Producers have promised that there will be #JusticeForBarb in series two, but that Shannon Purser's character is dead.

Dead. Definitely dead

"She had a creature - slug, worm, snake - coming out of her mouth," executive producer Shawn Levy told The Hollywood Reporter.

"I don't know that there's a bounce back from that."

He has also said that the search for Barb, and the impact of her death on her best friend Nancy, will play a big part in the second season.

The monsters will be even bigger this time

Series one's Demogorgon? Child's play compared to the multi-limbed beast seen in the teaser and poster for the new series.

Is this the Thessalhydra?

Fans have speculated that this giant monster is the Thessalhydra, a creature the child characters were seen battling during a game of Dungeons & Dragons in the first series.

There will be more slug vomiting

After Will Byers was rescued from the Upside Down at the end of the first series, his happy family reunion was short-lived when he vomited a live slug into the drain.

And there's more where that came from.

Will Byers is safe - for now

Matt Duffer, who makes the show along with brother Ross, says the after-effects of spending time in another world will be a main theme in series two.

"Season one does almost feel like a big movie that comes to a sort of ending," he told The Hollywood Reporter in 2016.

"A lot of that was based on the character of Will and the repercussions of him being in this upside down world for a week. Exploring that would be the second season."

Actor Noah Schnapp, who plays Will, also told the magazine he hoped his character would become a villain in series two and would be vomiting more slug-like monsters (and perhaps worse) as the show progresses.

Not all the monsters are evil

So far, viewers have only seen dangerous creatures from the Upside Down, but season two will introduce a friendlier monster which forms a friendship with young character Dustin.

Dustin (right) develops a special friendship with a creature from another dimension

"It's a little creature I get to bond with," actor Gaten Matarazzo told Entertainment Weekly in February.

"It's obviously not from this planet or this dimension."

Hardcore fans have season two sussed

The names of series two episodes were revealed in September last year and fans formed theories from a handful of words.

Jonathan and Nancy face more monsters in the show's second season

Fans believe there will be more eggs from the Upside Down, that we'll learn the secrets of the slug that Will vomited and of Eleven's power - and the show's producers are impressed with what fans have come up with.

"Some of the fan theories online are amazing," Matt Duffer told The Hollywood Reporter.

"Most are wrong, but I've read a few that are right or very close.

"Some of these theories are elaborate and smart."

So, when is it back?

Episode one of the new series is set on Halloween and the young cast are dressed as Ghostbusters

The second season of Stranger Things was expected to land on Netflix on Halloween, but the new poster confirmed it would land a little sooner - on 27 October.

This will give fans a few extra days to get their season two outfits sorted for the 31st.

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