Stranger Things season 5 made a huge reveal about the Upside Down and its origin, and looking back, there were a couple of clues to this big twist.

Nine years later, fans are finally getting answers to long-awaited questions regarding the Stranger Things universe — including what the Upside Down actually is. The revelatory moment arrives during ...

Stranger Things has been about the Upside Down since the very beginning. It’s the scary, twisted version of our world that spawned all the evil that has driven the action for five seasons. Or so we ...