Chapter Seven: The Bite - S3-E7
Revealing mistake: When Joyce and Hop get out of the car at the fair, you can see Hopper's, Smirnoff's, and Joyce's breath as if it was cold out, despite being a July 4th fair. The grass looks dead as well. (00:30:20)

Starring: Winona Ryder, David Harbour, Millie Bobby Brown, Finn Wolfhard, Dacre Montgomery
Chapter Seven: The Bite - S3-E7
Revealing mistake: When Joyce and Hop get out of the car at the fair, you can see Hopper's, Smirnoff's, and Joyce's breath as if it was cold out, despite being a July 4th fair. The grass looks dead as well. (00:30:20)
Chapter Two: The Weirdo on Maple Street - S1-E2
Factual error: When Steve and Nancy are making out, the intro to "A Hazy Shade of Winter" by The Bangles plays. While the original version of the song was released by folk-pop duo Simon and Garfunkel was released in 1968, the version heard here was released in 1986, 3 years after the scene takes place. (00:52:30 - 00:55:40)
Mike Wheeler: Mom, if anyone asks where I am, I've left the country.
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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