In Stranger Things season 1, Will is found near the very end of the season, in the finale episode “Chapter Eight: The Upside Down.”

When they find Will

  • Joyce Byers and Chief Jim Hopper locate Will in the Upside Down, where he has been taken by the Demogorgon.
  • In the in‑story timeline, this rescue happens on the nights of November 12–13, 1983, a week after his disappearance on November 6.

How they find and save him

  • Eleven uses a sensory deprivation setup at Hawkins Middle School to psychically locate Will (and Barb) in the Upside Down, giving the adults a clear idea of where he is.
  • Joyce and Hopper then physically enter the Upside Down through a gate at Hawkins Lab, find Will unconscious and restrained by a tendril, remove it, and Hopper performs CPR until Will starts breathing again.

What happens after

  • After they bring him back, Will is hospitalized and later examined at Hawkins National Laboratory because of lingering effects from his time in the Upside Down.
  • Those after‑effects, including visions and a connection to the Mind Flayer, become a key part of his storyline in season 2 and beyond.

Information gathered from public forums or data available on the internet and portrayed here.