'Eleven, Are You Listening?' Stranger Things Season 4 Teaser Returns to Hawkins Laboratory
Stranger Things fans, it's time to head back into the Upside Down.
Set in what appears to be the Hawkins National Laboratory in the past, the teaser opens with a group of children playing together in a room. Some play chess, while others ask questions of a Magic 8-Ball.
Midway through the clip, Matthew Modine's Dr. Martin Brenner, also known as "Papa" in the series, is seen walking into the room, greeting the kids. "Today, I have something very special planned for you," he tells the group as the camera pans down the hall to a room with the number 11 on it while a voiceover of someone taking deep breaths plays.
As the background music becomes more and more intense, the teaser then ends with Modine's character saying, "Eleven, are you listening?" before a shot of Millie Bobby Brown's Eleven opens her eyes.
Stranger Things features an ensemble cast of characters who battle against entities from the Upside Down. The first three seasons have shattered viewership records for the streaming service and been met with critical acclaim.
Set to return for season 4 alongside Brown's Eleven is Winona Ryder (Joyce Byers), Gaten Matarazzo (Dustin Henderson), Finn Wolfhard (Mike Wheeler), Noah Schnapp (Will Byers), Caleb McLaughlin (Lucas Sinclair), Natalia Dyer (Nancy Wheeler), Charlie Heaton (Jonathan Byers), Maya Hawke (Robin Buckley), Sadie Sink (Max Mayfield), Joe Keery (Steve Harrington), Priah Ferguson (Erica Sinclair) and Cara Buono (Karen Wheeler).
Dacre Montgomery will not be reprising his role as Billy Hargrove, who sacrificed himself in the season 3 finale to save Eleven from the Mind Flayer.
Season 4 will also welcome a slew of new characters, including three series regulars: Jamie Campbell Bower, Eduardo Franco and Joseph Quinn. Joining in recurring roles are Sherman Augustus, Mason Dye, Nikola Djuricko, Tom Wlaschiha and Robert Englund.
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Hopper's return was confirmed in February 2020 when Netflix dropped a teaser titled, "From Russia with love …" In the short clip, a snowy scene showed workers constructing a railway line — and one of them was revealed to be a bald Hopper.
In an interview with PEOPLE, Harbour teased that in the new season, audiences will "see a lot of your favorite characters doing the thing that you love them for ... but you'll also see them twist it and turn it into other colors and other flavors."
Harbour also said that fans will "get to see an entirely other color" of Hopper in season 4. "This season is my favorite because he really is going to show you some new colors and what he's really made up of," he said.
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Netflix announced in October that Stranger Things had resumed production on season 4 after the pandemic halted filming earlier in the year. The show was a month into production on the upcoming season when the pandemic hit the U.S. in March 2020, with the scripts polished and ready to go, PEOPLE previously reported.
Prior to pausing production, the cast got together in Atlanta for their first table read.
And there's more good news for Stranger Things fans: co-creator Ross Duffer has already confirmed that the series will continue past season 4.
"We know what the end is, and we know when it is," he told The Hollywood Reporter in August. "[The pandemic] has given us time to look ahead, figure out what is best for the show. Starting to fill that out gave us a better idea of how long we need to tell that story."
"We've had a lot more time to work on the scripts," Matt Duffer added. "For the first time, we have all the scripts written and we're able to look at it as a whole piece and make adjustments."