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Explains the reason why Gwen died. Also explaining that Gwen died in the 1973 Spiderman issue. Same death, different scenario.
"The Night Gwen Stacy Died"
Skip to Controversy, Behind the scenes.
It says that the writers of the comic killed Gwen Stacy because they sidn't know what to do with her anymore. Also explains more about the question.
Gwen Stacy in the Amazing Spiderman 2 was killed because of this exact same shocking issue. One of the most iconic deaths in Marvel history. They had to find a way to re-create this iconic death in the movie, and still stay faithful to the comic.