Stranger Things teases an upcoming season 4 update in an eerily mysterious video. Arguably Netflix's biggest ongoing original series, Stranger Things last dropped new episodes in the summer of 2019. The end of season 3 left fans with the cliffhanger that Jim Hopper (David Harbour) is alive and being held in a Russian prison, and excitement for season 4 has only grown since then. Sadly, however, progress on Stranger Things' fourth run has been hindered by the coronavirus pandemic. Filming kicked off in early 2020, but it wasn't long before everything had to be shut down because of the pandemic.

Stranger Things season 4 resumed filming later in the year, but star Gaten Matarazzo said in January it's been progressing slower than normal. As of late March, production was still ongoing, and Finn Wolfhard said last month he believes the new episodes will premiere in 2022. This is far later than what audiences had been expecting, but all signs point to this season being worth the wait. Matarazzo, Wolfhard, and other Stranger Things stars have hyped up the darker tone of season 4, with some even saying it's the most mature one yet.

Related: Why Stranger Things New Set Photos Are Good News For Season 4

At long last, some kind of update appears to be on the horizon. Exactly what that is, though, remains to be seen. Wednesday afternoon, the official Stranger Things YouTube account shared a nearly two minute-long video titled "HNL Control Room." HNL refers to the Hawkins National Laboratory, aka the site of Eleven's (Millie Bobby Brown) experimentations and the gate to the Upside Down. The video itself shows a bank of staticky video monitors. At various intervals, one comes to life and shows a snippet of some kind of room. Though said room is empty, it's clear something serious has gone down within it, as bloody splatters and smears can be seen. Check it out below.

The description for the video says they will be "back in service tomorrow at 9:00AM ET." The very specific timing seems to indicate something is coming tomorrow morning, but just what? The easiest guess could be a Stranger Things trailer of some kind, which would be eagerly welcomed by fans. However, it could also be that we'll figure out just what happened in the rainbow-walled room of the Hawkins lab. Since that is the focus of this particular video, which leaves more questions than answers, it feels like it is setting something up that specifically pertains to the lab. Perhaps this is a major clue for Stranger Things season 4.

Whatever it is, there won't be much of a wait before all is revealed. Stranger Things fans just might have to tune into the channel at 9am ET tomorrow to figure out just what is going on. Since production extended so far into this year, it likely isn't some kind of release date announcement, but footage isn't off the table. After all, an early trailer of Hopper at the prison was released well over a year ago. Maybe tomorrow will bring another Stranger Things clip to help tide fans over until season 4 arrives.

More: Stranger Things Fan Theory: The Upside Down Is An Inscape

Source: Stranger Things