'Stranger Things 4' part 2 trailer teases end of Hawkins: What to know about penultimate season

It's been said good things come to those who wait — and "Stranger Things" fans sure know a thing or two about waiting.

Netflix show's creators Matt and Ross Duffer, AKA the Duffer Brothers, announced in a letter to fans February 17 that the fourth season will drop this spring — and that it will also be "the beginning of the end" of the beloved series.

Season 4 picks up six months after Season 3 with the group of friends separated for the first time and "navigating the complexities of high school hasn't made things any easier," according to a plot synopsis provided by Netflix.

"In this most vulnerable time, a new and horrifying supernatural threat surfaces, presenting a gruesome mystery that, if solved, might finally put an end to the horrors of the Upside Down," the summary reads.

Here's everything we know about the penultimate season.

'Stranger Things' Season 4 releases in May

Running almost double the length of previous seasons, Season 4 will be released in two volumes, the brothers said, with the first coming May 27 and the second July 1.

"So that's the good news. It's coming soon. And it's bigger than ever," they wrote.

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The part one trailer lives up to the hype

The first "Stranger Things" Season 4 trailer dropped April 12 and it's living up to the Duffer brothers' hype. The clip shows grown up Mike (Finn Wolfhard), Dustin (Gaten Matarazzo), Lucas (Caleb McLaughlin) and Max (Sadie Sink) heading into high school as Eleven (Millie Bobby Brown) and Will (Noah Schnapp) are in California. The teens are adjusting to adulthood while the Upside Down is crumbling and more monsters are coming through.

"A war is coming. I'm afraid your friends in Hawkins are very much in the eye of a storm," a powerless Eleven is warned. "I don’t know how to say this other than just to say it — without you, we can’t win this war."

As the kids prepare to go to war, the trailer shows that Chief Jim Hopper (David Harbour) is still alive and is also being forced to fight. However, in his case he's in a Russian prison tasked with fighting a Demogorgon. "I was convinced I was put here for some other reason. Maybe I can still help. Even if it's the last thing I do," he says.

The part two trailer puts Hawkins' teens to the ultimate test

Part two of "Stranger Things" season four includes two more "super-sized" episodes debuting on July 1. The Hawkins teens are up against their scariest monster yet: Vecna, a powerful wizard set who exacerbates the trauma of their victims before their death. Netflix released a new trailer June 21 set to the tune of Kate Bush's "Running Up That Hill," showing Eleven working up the strength of her once-lost powers to save her friends.

"My friends need me," she declares as "Papa" tells her she's not ready.

Will tells Mike Vecna will not stop "until he's taken everyone" before the teens go off into a dangerous battle. Robin (Maya Hawke) adds, "It might not work out for us this time."

Tears, explosions and the return of old monsters close out the trailer as Vecna says, "Your friends have lost."

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Beloved character Chief Jim Hopper's unexpected return

It's been two years since Netflix released the first teaser trailer for Season 4. The 50-second clip zoomed in on a snowy work camp with barking dogs and armed guards. One of the workers? None other than Hopper, whose fate was left a mystery at the end of Season 3.

"He is imprisoned far from home in the snowy wasteland of Kamchatka, where he will face dangers both human ... and other," the Duffers said of Hopper at the time. "Meanwhile, back in the states, a new horror is beginning to surface, something long buried, something that connects everything."

Expect a fifth season of 'Stranger Things'

The new season will also be the show's second-to-last.

"Seven years ago, we planned out the complete story arc for 'Stranger Things,' " they wrote. "It proved too large to tell in four (seasons) — but, as you'll soon see for yourselves — we are now hurtling toward our finale. Season 4 will be the penultimate season; season 5 will be the last."

But don't worry, "Stranger Things" fans. The Duffer Brothers assured there are "still many more exciting stories" to come, including new mysteries, adventures and characters.

The third installment of the sci-fi series, which released in July 2019, was the second-most-popular title on Netflix for 2019, the streaming service said.

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Contributing: Anika Reed, Naledi Ushe

This article originally appeared on USA TODAY: 'Stranger Things' 4: Trailer, season release dates, everything to know