Fans who have spent years watching the Marvel movies in order know that plenty of well-known actors have gotten in on the fun, including Jake Gyllenhaal, who played Mysterio in Spider-Man ...

So, how exactly did the Stranger Things star Sadie Sink become the pivotal piece in this emotional puzzle? Let’s break it down.

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The biggest surprise from the trailer is the appearance of Mysterio (Jake Gyllenhaal), traditionally a stuntman and special effects expert who is a frequent foe of Spider-Man in the comics.