Vecna is the main antagonist from the fourth season of Stranger Things. He is portrayed by Jamie Campbell Bower as an adult and by Raphael Luce as a child.
A fearsome sentient creature aligned with the Upside Down, Vecna had humble origins as the human Henry Creel. After moving to a new home in Hawkins in March 1959, the young Henry discovered he had remarkable psychokinetic abilities, and could alter the perception of others. Motivated by a nihilistic and misanthropic philosophy, Henry used his powers to psychologically torture his family, eventually killing his mother and sister, and then framing his father for these crimes, which drove him to madness.
These events would draw the interest of Dr. Martin Brenner, who took him to Hawkins National Laboratory to be studied; Henry was designated 001, becoming the laboratory’s first test subject. Brenner implanted Soteria into Henry’s neck, a miniature device that suppressed his powers and tracked his every movement; in Henry’s own words, he had become a ‘prisoner’. In time, Henry became one of several orderlies who assisted Brenner and attended to the lab. Brenner would go on to replicate Henry’s powers in a number of child test subjects, who also had their movements restricted to the lab’s confines.