“Stranger Things” last graced our Netflix screens three long years ago. And the spooky hit is finally returning with its (supersized!) fourth season, starting this Friday, May 27. If you’re anything like us, however, you might need a little refresher as to what exactly went down in Hawkins, Indiana over the course of the show’s first three seasons. FOX TV critic Caroline Siede is here to catch you up on the Upside Down.