What’s inside the briefcase that Henry/Vecna ​​finds in Stranger Things season 5?

The following article contains spoilers for “Stranger Things” season 5, volume 2.

There have been quite a few mysteries in the “Stranger Things” timeline, but Season 5, Volume 2 contains a mystery that fans need some extra help understanding. While trapped in the mind prison of villain Vecna ​​(Jamie Campbell Bower), Max (Sadie Sink) and Holly (Nell Fisher) see a much younger version of Vecna ​​when he was still a human child named Henry Creel. Holly watches Vecna’s memory as he finds an injured scientist, then kills him with a rock before taking the man’s briefcase. When he opens it, smoke starts coming out, but Max comes to save Holly before we can see what happens next. There’s not really any other mention about it, but it’s clear that this case is important. So, uh, what is it?

The answers are contained in the “Stranger Things” prequel play, “Stranger Things: The First Shadow,” which premiered in London in 2023. In the play, we learn that young Henry found and opened a briefcase that transported him to Dimension X, where he was infected with Mind Flayer particles, forever altering his DNA. Since Vecna ​​is the big bad of “Stranger Things,” revealing her origin story in a stage play and only alluding to it in the streaming series seems a bit silly. The show told us he was the original super-powered being in our dimension and even explained how his blood was used to create the other psychic children, but leaving out his origin is a bit strange. Indeed, Season 5, Volume 2 was a bit frustrating overall, and choices like this definitely contribute to the problem.

The briefcase serves as the mechanism for Henry to travel to Dimension X and become infected by the Mind Flayer, leading to the eventual creation of the wormhole that is the Upside Down, but absolutely none of this is explained in “Stranger Things”. Instead, it’s all laid out in “Stranger Things: The First Shadow,” which adds even more lore to the already dense “Stranger Things” compendium. Having a spinoff play is great, but turning it into the knowledge you need to fully appreciate “Stranger Things” is serious horse hockey. People just want to see what happens to their favorite characters, and adding more and more confusing lore and expecting everyone to take apart the puzzle box is deeply irritating.

In “The First Shadow” we learn that the briefcase is stolen technology that accidentally transported some men to Dimension X and that Dr. Brenner’s father (Matthew Modine) was part of that experiment, which made Dr. Brenner so obsessed with Dimension This was all done by injecting Henry’s blood into pregnant women, infecting the newborns with Mind Flayer particles. This all seems pretty darn important, so why was it only revealed in full in the play? Just like the adult actors who still play kids on “Stranger Things,” I’m too old to do my homework, especially when it comes to something that’s supposed to be entertainment.

“Stranger Things” season 5 will end on December 31, 2025 on Netflix.