Chapter One: The Hellfire Club - S4-E1
Question: At the beginning of the episode we see all the children in Hawkins' lab die because of Eleven. But what happened to her? Just what did she do that made her kill all of those people?
Answer: You see what happened in one of the later episodes in the season ("Chapter Seven: The Massacre at Hawkins Lab").
Answer: This is answered in a later episode so you should watch the entire season, but if you really want to know...SPOILERS She didn't, 1 (Vecna) killed all those children.
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