They find Will at the very end of Stranger Things season 1, when Joyce and Hopper cross into the Upside Down and locate him unconscious and barely alive in a cocoon-like nest. The show later confirms he is being kept in the Upside Down version of the Hawkins Public Library, hooked up to tendril-like vines connected to the monsters and Vecna.

Where Will disappears

  • Will vanishes on his bike ride home near the wooded shortcut the kids call “Mirkwood,” after encountering the Demogorgon.
  • The creature drags him into the Upside Down, the parallel version of Hawkins that sits on top of the real town.

How everyone starts searching

  • Joyce reports Will missing to Chief Hopper, kicking off the official police search around Hawkins, the woods, and the quarry.
  • The government lab fakes Will’s death by planting a fake body in the water, trying to shut down the investigation and keep the Upside Down secret.

Clues that Will is still alive

  • Joyce notices lights flickering in the Byers’ house and realizes Will can “talk” to her through electricity, using Christmas lights and letters on the wall to spell messages like “RIGHT HERE” and “RUN.”
  • Will also briefly communicates through radios and phone calls, convincing Joyce and later Hopper that he is alive but trapped somewhere else, not dead.

How they actually find him

  • Hopper and Joyce break into Hawkins Lab and force their way to the Gate to the Upside Down, then step through into the dark mirror-version of Hawkins.
  • Following signs of the Demogorgon and its lair, they reach the Upside Down Hawkins Public Library, where Will is wrapped in organic vines and a slimy pod-like growth, with a tendril in his mouth.

What’s going on with Will there

  • In that nest, Will is basically being used as an incubator/host, with the vines feeding particles into him—a connection later tied to Vecna and the Mind Flayer.
  • Joyce and Hopper rip the vine out, perform CPR, and manage to revive him, which is why Will survives but later still feels a lingering connection to the Upside Down.

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