This article contains spoilers for Stranger Things season 4.
Stranger Things season 4's main villain, Vecna, is ultimately revealed to be Henry Creel — Dr. Brenner's "Number One" at the Hawkins Lab. The story of Stranger Things is, surprisingly, rooted in the real world — specifically in the CIA's Project MKUltra, a secret mind control program that was launched in 1953. The experiments being conducted by Dr. Brenner at Hawkins are supposed to be an offshoot of Project MKUltra, one that has unwittingly threatened the entire world.
Dr. Brenner's experiments have always been mysterious. It's long been unclear how he realized certain procedures could be used to ensure children were born with the potential to develop unusual powers, including telekinesis, telepathy, and illusion casting. The sheer scale of Eleven's success was demonstrated in Stranger Things season 4, which revealed he had created no less than 14 superhuman children. Curiously, though, the identity of his first test subject — his "Number One" — was a secret kept even from the other children.
Related: Stranger Things Season 4 Cast & Character Guide
Stranger Things season 4 finally unraveled the mystery, with episode 7 revealing the true identity of Number One. In a shocking twist, it turned out Number One is in fact the new villain from the Upside Down, Vecna. Stranger Things has always been quite open about drawing inspiration from superhero comics, and season 4 exploits a classic trope in which Eleven must face a twisted mirror image version of herself.
Dr. Brenner's children were granted powers by treating their mothers with psychedelic drugs during pregnancy. Henry Creel appears to be different, however; there's no evidence his mother ever experimented
Read more on screenrant.com