This article contains spoilers for Stranger Things 5, Volume 1, including details about Vecna that hail from Stranger Things: The First Shadow. If you don’t want to read any of that, head to our spoiler-free review of Stranger Things 5, Volume 1 instead and wait as long as you need to until you’re ready to dive into the worst memory of Henry/Vecna/1.
What Is Vecna/Henry Creel’s Worst Memory on Stranger Things 5?
Stranger Things 5, Volume 1 takes us into a place we really didn’t expect to see that much of, the mind of Vecna/Henry Creel. After Vecna flayed Max at the end of Stranger Things 4, she died, but Eleven brought her back to life. While Max’s body remains in a coma in the real world of Hawkins, her consciousness finds itself trapped somewhere else, inside the prison of Henry Creel/Vecna’s mind, a location that manifests as a maze of Vecna’s memories. For a long time, Max tried to navigate her way out of Vecna’s memory palace prison, but just when she thought she’d be able to break free into the real world, Vecna found her and began to chase her down. Max only escaped Vecna on Stranger Things 5 by accidentally running into a place that he couldn’t follow her, his worst memory.

The Physical Details of the Cave in Vecna/Henry’s Memory
But what is Vecna/Henry Creel’s worst memory in Stranger Things 5, Volume 1? The show gives us a few details. Physically, we see a red rock formation with a cave in its center, which forms most of the memory; scorpions dot the area around it, and the sun blazes down over it, making us feel like we’re in the desert. Max even shows Holly that the memory “comes with a view,” which lets us literally see the landscape of mountains, rocky ridges, and barren stretches around the cave. Geology nerds will know this image points to Nevada’s specific landscape.

The Emotional Weight of the Cave in Vecna/Henry’s Memory
Emotionally, though, the question of Henry’s worst memory is a different story. Max tells us that as she ran into the cave with Vecna on her heels, something about this memory stopped him short. She shares, “I’ll never forget the look on his face that day. He was scared. More than scared, he was terrified. There’s something about this cave, this memory. He won’t come in. In here, I’m safe.” For whatever reason, Vecna/Henry Creel feels so terrified of whatever lurks in his worst memory that it completely disables him. But Stranger Things 5 doesn’t reveal what hides in the cave for Vecna—instead, that knowledge comes to us from a different source: the Stranger Things play, Stranger Things: The First Shadow.
Vecna’s Worst Memory Comes Right From the Stranger Things Play, The First Shadow
It’s highly likely that many Stranger Things fans have never seen The Stranger Things play, The First Shadow. So, we bet in Stranger Things 5, Volume 2, the series will make sure to flesh out some of this information. But for the curious, Stranger Things: The First Shadow tells us exactly what memory waits for Vecna/Henry in the Nevada cave. Here’s what the play reveals to us about Vecna/Henry Creel’s worst memory.
Stranger Things: The First Shadow Explains Henry First Made Contact with Dimension X in a Nevada Cave When He Was 8

In the Stranger Things play, Dr. Brenner reveals to the audience and a young Henry Creel/Vecna, “Your mother tells me that you went missing after your eighth birthday for about…12 hours nearby a military base in Lincoln County, Nevada. You were found outside a cave system with a wound on your left hand. No memory of what happened.” And later adds, “At the military base. That’s where I work, Henry. Where, a few years back, right around your eighth birthday, actually, one of the doctors working with the captain was revealed to be Russian spy. He escaped the facility. The Russian’s body was found two days later in a cave system. Right outside Lincoln County… This doctor had taken something… Something a bored child might be curious about. Something… from beyond our world.”

Additionally, Brenner reveals he found Henry’s spyglass, the very one Holly takes from the Creel Memory House in Stranger Things 5, inside the cave system by the dead Russian spy and the empty box.
Henry’s Worst Memory Is of Being Flayed By the Mind Flayer

Stranger Things: The First Shadow makes it clear that a young Henry Creel came into contact with Mind Flayer particles in the Nevada cave and was first flayed by the Mind Flayer at this point. The Mind Flayer particles, the Stranger Things play explains, literally changed his blood, transforming him into something other than human and later allowing Brenner to create 11 and the other children with powers, like Kali/Eight. The play also confirms that Henry Creel first visited Dimension X during his flaying, via the Nevada cave/Mind Flayer particles he found there. Once again, Dimension X is the “pure” dimension from which the Mind Flayer and demogorgons come, and which Eleven will later send Henry/Vecna back to. (Note: Dimension X is different from the Upside Down, but it’s not yet clear how.)
Taken altogether, the Stranger Things play, The First Shadow, confirms that Henry/Vecna’s worst memory, which we visit with Max in Stranger Things 5, Volume 1, is his memory of being flayed by the Mind Flayer in the Nevada Cave and going to Dimension X for the very first time, changing his life forever.
Why Is Vecna’s Worst Memory and His Nevada Cave Important in Stranger Things‘ Final Season?

Importantly, Stranger Things: The First Shadow draws a distinction that the Stranger Things TV series does not. It creates a stark difference between Henry Creel/Vecna and the Mind Flayer. In the Stranger Things TV show, the Party comes to believe that Henry and the Mind Flayer are one and the same. However, the Stranger Things play takes pains to reveal that Henry Creel is a troubled human child, manipulated and driven mad over an extended period of time by both the evil entity of the Mind Flayer, who actively whispers posion in his ear, and the power-hungry Dr. Brenner. Henry Creel/Vecna is capable of love when he is young, he is capable of goodness, and critically for some period of time, he wants to fight the Mind Flayer’s influence, though he eventually succumbs to it.
Stranger Things 5 emphasizes to us that Henry Creel/Vecna’s worst memory, the one that hurts him the most, that makes him feel fear, is actually the memory of him first receiving his powers and being changed by the Mind Flayer, which begins to point us to a new narrative. Seeing Henry’s worst memory and the Nevada cave scare him so much, even as Vecna, reminds us that a part of Henry Creel is still in there, and he may not be as allied with the Mind Flayer as we initially thought. In fact, the Mind Flayer is his greatest nightmare on Stranger Things.

After all, to follow Holly’s A Wrinkle in Time metaphor, a disembodied brain with telepathic powers called IT rules Camazotz, but the Black Thing controls it, itself. Ultimately, the inclusion of Henry Creel’s worst memory points loudly to Vecna not really being the big bad on Stranger Things. Instead, Vecna’s worst memory suggests the true villain of Stranger Things is really the Mind Flayer.
The Mind Flayer Is Vecna’s Worst Nightmare, But What Will That Mean on Stranger Things?
So, what does that mean for Vecna? Has the Mind Flayer controlled Vecna all along? If we believe Vecna’s worst memory, kind of, because Vecna was just an eight-year-old child when the Mind Flayer first corrupted his mind in the Nevada cave, it was hardly a fair fight. That said, at some point, Vecna actively embraced the evil powers the Mind Flayer gave to him. But it does feel like some part of him resents them. Could we see a face-off between Vecna/Henry and the Mind Flayer in season five of Stranger Things? That certainly feels possible. Some theories even speculate that Vecna might try to go back in time to make sure he’s never flayed to begin with.

Ultimately, it’s hard to say what Vecna’s up to. But one thing we do know is that by harkening back to Stranger Things: The First Shadow and making the Nevada cave memory a painful part of Vecna’s existence, Stranger Things does want us to see Vecna as something other than an agent of pure evil.