Fans can breath a sigh of relief that 'Stranger Things' season 4 is well and truly on the way.

'Stranger Things' season 4 is officially in production, having resumed filming last October after a six month hiatus.

We now have a new cryptic, minute-long teaser to give us a hint of what's on the way...

It would seem that the kid experimentations which Eleven (Millie Bobby Brown) was once a part of, will play some role in the upcoming episodes.

Dr. Martin Brenner, played by Matthew Modine, is also back, it seems.

Watch the teaser below, posted on the official 'Stranger Things' Youtube channel and other social platforms, and see for yourself.

It's not the first teaser for 'Stranger Things' season 4 eaither.

Previously, an official video revealed that Hopper (David Harbour), believed to have died in the season 3 finale, is actually alive, and imprisoned by Russians.

There's very little to go on as to what the new season will be about, though creators the Duffer brothers offered a few hints previously.

Fans have been patiently waiting, given the third season of the sci fi Netflix series debuted nearly two years ago...

No premiere date for the new season yet, as it is still in production.