The Duffer Brothers just nuked fan theories: Billy Crudup almost played Hopper, not David Harbour. The hated Season 2 episode 207 was never a spin-off pilot.

Steve’s tower fall forced the show’s first-ever reshoots. David Harbour hated the original title, "Montauk." Eleven’s final "heartbeat" sound?

Just a distorted brick. The Upside Down is officially wilder than we imagined.