🔗 Share this article

Throughout a large portion of season 5 of *Stranger Things*, Holly Wheeler and Max Mayfield are imprisoned inside a mental fortress constructed from the past of Henry Creel. The search for an escape route in episode 6 leads them to experience a traumatic incident from Henry's early years—an event that potentially carries the key to defeating him permanently.

Spoiler Warning: This article details significant events for the second part of the final season.

A Journey Into the Tunnel

When she finds Max in the mental landscape dubbed Camazotz, Holly discovers she is taking refuge in a grotto that Henry is terrified of. An accidental discovery a telescope found in Henry's old home allows Holly to realize that the true terror lies outside of the cave. Matching her view through the cap, she and Max suddenly fall into a abandoned tunnel.

There, they witness a Henry as a boy encounter an wounded, fearful individual. As the boy offers aid, the man panics and shoots, hitting him in the hand. To protect himself, Henry strikes the man down with a rock. "Did this make Henry evil?" Holly wonders aloud. It was a factor, but the act wasn't just a defensive killing.

Similar to other plot points of the final season, the full story behind the events in the tunnel originates in the theatrical production Stranger Things: The First Shadow.

The Philadelphia Experiment and Secret Science

*The First Shadow* opens with the infamous Philadelphia Experiment, which reportedly teleported a vessel into a dimension later called the Abyss. The ship was attacked, and the only one to return was the ship's commander, who came back in a vegetative state with an entirely new blood.

This man's son, the future Dr. Brenner, sought to replicate this phenomenon in Nevada. But a disloyal lab worker took experimental components to give to the Soviets, who were keen to start their parallel research. This spy in the cavern is the one who stole the materials.

So, What's in the Case?

Given what is understood of his research, the container almost certainly contained some of Captain Brenner's infected blood. As shown, Henry is already bleeding. Exposure likely occurred upon opening the case, which triggered the development of his psychic abilities—abilities he would genetically impart to the test subjects Brenner would experiment on.

A second theory, the container could have held dark matter that later made its way to the secret facility, where it acts to anchor the parallel world. *The First Shadow* reveals that young Henry was transported in the Abyss, coming back 12 hours later fundamentally changed. As a youth, he fights the control of a dark entity, reminiscent of how Will Byers was controlled by the entity in an earlier season.

A Weaponized Emotion

The reason Henry avoids the cave associated with the mine highlights how deeply scarring the event was for him. While he orchestrates the Hive Mind and works to collapse the Abyss into Hawkins, a fragment of his psyche lingers. Vecna uses fear, and the narrative points to a showdown between Vecna and Will, who has confronted his personal demons to gain strength.

Will's growth has neutralized a key tactic of Vecna. More importantly, Will now is aware of what the monster's own weakness, and this may grant a decisive edge in the ultimate battle ahead.