Will Byers gets to the Upside Down when he is attacked and taken by the Demogorgon on his bike ride home in the first episode of Stranger Things, effectively being pulled through an unseen rift between worlds. The show leaves the exact mechanics of that rift vague, but later lore and tie‑in comics strongly support that the creature drags him directly into the parallel dimension rather than using a clearly visible “portal” like the ones seen later.

Quick Scoop

  • Will is riding home from Mike’s house at night when the Demogorgon appears on the road near Mirkwood and knocks him off his bike.
  • He runs to his house, loads his dad’s rifle in the shed, and faces the creature; after this confrontation he vanishes, having been taken into the Upside Down.
  • The most accepted explanation is that the Demogorgon can phase or “tear” reality around it, briefly opening a passage and dragging victims straight into the Upside Down, which is what happens to Will.

What the Show Directly Shows

  • On screen, viewers see: bike crash, Will barricading himself at home, fleeing to the shed, and then the lights flicker as the Demogorgon closes in before Will disappears from the normal world.
  • The series never shows a clear portal at that moment the way it does at Hawkins Lab or the tree near Steve’s house; the cut implies an off‑screen transition as the monster seizes him.

Extra Details From Tie‑In Material

  • In the officially licensed comic “Stranger Things: The Other Side,” Will fires the rifle at the Demogorgon but is still transported into the Upside Down version of his world, confirming that the attack in the shed is the moment of crossing.
  • The comic follows his journey hiding in locations like the Upside Down Castle Byers, reinforcing that he arrives there directly after the shed confrontation, not by wandering into a separate portal later.

Fan Theories and Newer Lore

  • Some fans argue that because later seasons reveal Vecna as the mastermind behind events in Hawkins, he may have “orchestrated” Will’s abduction by controlling the Demogorgon, using Will as a long‑term pawn.
  • Others think Will was targeted because of a special sensitivity or latent connection to the Upside Down, which might explain both why the creature followed him so far and why he later has a lingering psychic link to the Mind Flayer.

Upshot for “How Did He Get There?”

  • Canonically: Will is attacked by the Demogorgon during his bike ride and dragged into the Upside Down during the shed scene, via a localized tear between dimensions created by the monster’s presence.
  • The exact physics are never fully spelled out on screen, but within the story’s rules it functions like an invisible, monster‑made gateway that pulls its victim straight into the mirror world. 🕯️

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