Will is found alive in the Upside Down and rescued in episode 8 of Stranger Things season 1, titled “Chapter Eight: The Upside Down.”

When Will disappears

  • Will Byers vanishes after biking home from a Dungeons & Dragons game in episode 1, “Chapter One: The Vanishing of Will Byers.”
  • A fake body is later “discovered” in the quarry, planted by Hawkins Lab to cover up that a creature from another dimension took him.

When Will is actually found

  • Joyce and Hopper track Will to the Upside Down by using the sensory‑deprivation tank with Eleven and following the creature’s lair.
  • Hopper performs CPR on Will and brings him back to life in the Upside Down, after which he is taken to Hawkins Lab for medical treatment.

After Will’s rescue

  • By the end of season 1, Will is home but still affected, coughing up a slug-like creature in the bathroom and briefly flashing back to the Upside Down.
  • This lingering connection to the Upside Down and the Mind Flayer drives much of his story in seasons 2 and 3.

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