Although Stranger Things may be over, Netflix and the Duffer Brothers aren’t yet finished expanding this world’s mythology beyond Hawkins. After all, the seeds have already been planted for the Duffers’ mysterious spin-off series.

Stranger Things’ series finale rightly kept its main focus on wrapping up the five-season saga that first began nearly a decade ago in 2016. However, the Duffers have recently revealed the one scene that helps set up their future spin-off, so here’s our full breakdown and everything we know so far.

Stranger Things’ Briefcase Scene In The Series Finale Sets Up The Spinoff

Maksim Blatt as Young Henry in Stranger Thing Season 5, opening a brief case in dark caves with blood on his face.Credit: Courtesy of Netflix

The Stranger Things finale includes a flashback to Henry Creel’s traumatic childhood in Nevada, where he encounters a mysterious man carrying a locked briefcase within a cave system near his house.

After being shot in the hand, young Henry beats the man into submission before discovering the contents of the case: a black glowing rock that enters Henry’s wound, resulting in his first contact with The Mind Flayer in The Abyss. Following the finale’s release, The Duffers confirmed in an interview with Variety that this black rock will serve as a key foundation for their upcoming spin-off.

Connecting to events that were first revealed in The First Shadow stage play, it should be fascinating to learn exactly what this stone is and how it will expand the world of Stranger Things in brand-new ways.

How The Upcoming Stranger Things Spinoff Can Answer Lingering Lore Questions

Henry Holding Mysterious Rock in Stranger Things 5

While Stranger Things’ series finale was emotionally satisfying with strong conclusions for many of its characters, there are plenty of lingering questions when it comes to the greater lore. As such, a spin-off centered on the black rock and its apparent ties to The Mind Flayer could go a long way in answering some long-standing mysteries.

Perhaps the spin-off is a prequel, offering greater insights into the work that was done by Doctor Brenner in Nevada as well as the experiments conducted by his father on the USS Eldridge. The elder Brenner and his men were the first known humans to interact with The Mind Flayer (as confirmed by The First Shadow) inspiring his son’s work in Nevada and later experiments in Hawkins.

Likewise, we also know from The First Shadow that the scientist who encountered Henry stole the stone from Brenner’s Nevada project and was a Russian defector. Perhaps the spin-off could reveal more about the Russian subplot that was very much dropped in Stranger Things 5.

Overall, the spin-off has the opportunity to answer several lingering lore questions, many of which don’t have to be answered in Hawkins nor with the original Stranger Things cast.

Will The Stranger Things Spinoff Feature Returning Characters?

Matthew Modine's Dr. Brenner looking intensely at El while kneeling in front of her in Stranger Things season 2

Because the story appears set decades earlier, familiar faces from Stranger Things will likely be scarce. The Duffers have already said as much, with the spin-off set to feature a completely new cast and even a new town, reinforcing the idea that this is a true spin-off and expansion into new territory, rather than being a continuation/sequel of Stranger Things itself.

However, that doesn’t necessarily rule out appearances from younger versions of key figures. If the black rock is a focal point, seeing younger Brenner at some point does seem plausible, as does the possibility of further exploring his father’s role.

Ultimately, the absence of returning Stranger Things characters may very well be the greatest strength of this mysterious new spin-off series. Free from expectations, the spin-off can genuinely be something fresh with the ability to take greater risks with new protagonists and a relatively new mythology to be explored.

Everything Else We Know About The Stranger Things Spinoff

Vecna in the Abyss in Stranger Things season 5Image via Netflix

Beyond this reveal about the black stone being a focal point, The Duffer Brothers have been intentionally vague about the spin-off’s broader direction thus far.

While the mysterious rock in the briefcase is central, they’ve teased that the show may introduce an entirely new town, fresh characters, and mythology that stands apart from what we’ve seen in Hawkins and the Upside Down across Stranger Things’ five seasons.

It’s also worth noting that the Duffers won’t serve as showrunners, though they remain creatively involved and are currently writing the story. This should help the spin-off feel even more like a fresher story, allowing new voices to shape the tone while preserving canonical oversight from the creators of this dynamic world/universe.

For the time being, the future Stranger Things spin-off remains a pretty big question mark. If it does indeed deliver on the promise of the briefcase and its black stone seemingly tied to The Mind Flayer, it could redefine the franchise, proving there’s more life and adventure to be had beyond Hawkins with new stories for both longtime fans and brand-new viewers.