Chapter One: Suzie, Do You Copy? - S3-E1
Factual error: When Dustin's toy collection "comes to life" (thanks to Eleven), one of the robots is the Transformer Ultra Magnus. Though it appears to be modified with a motorized engine that the actual toy didn't have, that's not the mistake, as there no reason Dustin couldn't have modified it. The error is that the season is set in July 1985, but Ultra Magnus wasn't released in the U.S. until 1986. (Yes, the toy was available as a Diaclone in Japan, but in a different color scheme. Dustin's has the coloring of the U.S. version, and even if he somehow ended up with the Diaclone version, it's highly unlikely he would have repainted a Japanese toy to resemble a Transformer he wouldn't know about the existence of yet, as the 'Transformers' animated movie wasn't released until August 1986).
Chapter Five: The Flayed - S3-E5
Factual error: When Eleven is handed M&Ms in the hospital she is given green and red. Red M&Ms were not reintroduced until 1987. (00:42:28)
Chapter Five: The Flayed - S3-E5
Factual error: When Hopper steals the yellow convertible at the gas station mini mart, the gas pumps have vapor recovery boots on the nozzles. Those weren't in use for another half decade.
Chapter Six: E Pluribus Unum - S3-E6
Factual error: When the Russian requests the cherry flavor and refuses to talk, he gets thrown out. At the back is an oil drum from the French energy company "Total." However that logo was introduced only in the mid 2000s. (00:11:55)
Chapter Eight: The Battle of Starcourt - S3-E8
Factual error: Because of the way radios work, when Suzie and Dustin are singing their duet they wouldn't be able to hear each other and the rest of the party would only hear a garbled mess. Per frequency only one radio should transmit at each time, so all the others can receive. If multiple radios are transmitting simultaneously, the signals will overlap and result in unintelligible noise. (00:35:53)
Chapter Eight: The Battle of Starcourt - S3-E8
Factual error: The value of Planck's constant used in the show, 6.62607004 is the value that was measured in 2014. The value that was in use in 1985 was 6.626176. The value was updated again in 2018, to 6.62607015.
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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