What happened to 001 in Stranger Things?
If you keep seeing "001" and want to know who that is — and how their story ends — you're asking about the most important character in the whole show.
001 is where everything in Stranger Things begins, and, as of the final season, where it ends too. Here's the full arc.
Spoilers throughout.
Who is 001?
001 is Henry Creel — the first child test subject at Dr Martin Brenner's (Matthew Modine) Hawkins National Laboratory, which is why he's labelled 001. As a boy in 1959 he discovered terrifying psychic powers and, under a dark influence, killed his mother and sister; his father Victor took the blame. Brenner brought him to the lab, fitted a suppressant chip in his neck to control his powers, and put him to work as an orderly. Using Henry's blood, Brenner created seventeen more powered children — including Eleven ( Millie Bobby Brown). Henry's blood is, quite literally, the source of Eleven's abilities.
How 001 became Vecna
In 1979, Henry tricked Eleven into using her powers to remove his suppressant chip. Freed, he slaughtered the lab's other children and staff and turned on Eleven — but she overpowered him and blasted him through a gate into the Upside Down. Marooned in that dimension, Henry slowly mutated into the monster the kids would later nickname Vecna, after a Dungeons & Dragons villain.
Across his time on the show, then, one character wears several names:
- Henry Creel — his birth name, the boy from the Creel House.
- 001 / One — his designation as Brenner's first subject.
- Vecna — the monster he becomes in the Upside Down.
- Mr Whatsit — the friendly 1950s guise he uses in the final season.
"They're all varying entities of himself." — Jamie Campbell Bower, The Hollywood Reporter, 2025
What he does in the final season
Stranger Things 5, released in three parts over the 2025 holidays, picks up around 18 months after Vecna tore four rifts across Hawkins. This time he hides behind a new face — Mr Whatsit, a Mr Rogers-style "imaginary friend" who lures children, including Holly Wheeler (Nell Fisher), into a dreamworld called Camazotz to use them as power sources for the Upside Down.
How 001's story ends
He loses. After a season-long build-up, the heroes finally corner him in the series finale, directed by creators Matt and Ross Duffer. Vecna is beaten, and it's Joyce Byers (Winona Ryder) who swings the axe that decapitates him and ends 001 for good. Jamie Campbell Bower, who played every version of the character, described that finale as the moment he finally felt Henry was human again.