The Mystery Within that Briefcase Henry Opens in the Hit Series?
Throughout a large portion of season 5 of the popular Netflix show, the young Holly Wheeler and Max Mayfield are imprisoned in a realm of memories forged from the memories of Vecna. The search for a way out in "Escape from Camazotz" has them witness again a traumatic incident from Henry's early years—an event that could contain the secret to his downfall permanently.
Spoiler Warning: This discussion reveals crucial plot points for *Stranger Things* season 5, volume 2.
A Journey Into the Cavern
After locating Max in the mental landscape dubbed Camazotz, Max reveals she is sheltering in a grotto that Henry avoids at all costs. By leaving the lens cap on a viewing device pilfered from Henry's old home helps Holly understand that the danger lies not within the cave. Matching her view to the cut-out, she and Max tumble into a subterranean passage.
They watch a young, eight-year-old Henry come across an man who is hurt and scared. When Henry tries to help, the man panics and shoots, hitting him in the hand. To protect himself, Henry kills the man with a rock. "Was this the turning point?" Holly wonders aloud. It was a factor, but the act went deeper than a defensive killing.
In keeping with mysteries of the final season, the significance of the mine shaft incident was first explored the theatrical production the prequel play.
A Naval Mystery and Secret Science
The play reveals the 1943 event, which allegedly sent a U.S. Navy ship into a plane dubbed the Abyss. The ship was attacked, and the sole survivor was the captain, who came back in a vegetative state with an altered blood type.
That survivor's offspring, a young Martin Brenner, attempted to recreate this phenomenon in the Nevada desert. However, a treacherous employee took experimental components to sell to the Russian agents, who were eager to begin their version of the tests. The man in the cavern is that employee.
So, What's in the Case?
Given what is understood of the doctor's experiments, the case would assuredly have some of Captain Brenner's infected blood. As shown, Henry is bleeding from his hand. Exposure likely occurred upon handling the contents, leading to the origin of his telekinetic gifts—powers he would inadvertently transfer to the kids Brenner would experiment on.
A second theory, the case could have held dark matter that eventually found its way to Hawkins Laboratory, where it acts to anchor the mirror dimension. The prequel shows that Henry was transported in the Abyss, coming back 12 hours later fundamentally changed. Throughout the play, he struggles with the influence of a dark entity, reminiscent of how Will was controlled by the entity in an earlier season.
A Weaponized Emotion
The reason Henry avoids the cave associated with the mine demonstrates how utterly horrifying the encounter was for him. Even as he orchestrates the collective consciousness and seeks to merge the Abyss into Hawkins, a part of him still exists. Fear is his tool, and the series is building toward a showdown between Vecna and Will, who has overcome his personal demons to fortify himself.
This journey has taken a weapon from Vecna. More importantly, Will now understands what his enemy truly fears, which could provide a key upper hand in the endgame conflict that awaits.