In a lab on the outskirts of Hawkins, Indiana in November 1983, a mysterious monster kills a scientist. While riding home at night from a ten-hour Dungeons & Dragons session, young Will Byers rides through the woods, but is kidnapped and goes missing.
When Will's mother and brother, respectively Joyce and Jonathan realize that he's missing the next morning, they go to Police Chief Jim Hopper, who tells them that Will has likely either been abducted by his absent father or is just running away. Joyce denies it, and Hopper (after noticing a few strange happenings going on) decides to go search for Will in the woods where he went missing.
Meanwhile, a short-haired girl ventures out of the same woods and into a local restaurant, where she, having never been in one before, starts to steal food from the owner. The owner chases her until he realizes who she is and gives her food, as well as calling social services. She doesn't speak, but the restaurant owner, Benny, spots a tattoo on her arm that reads "011" and begins to call the girl Eleven.
When social service agents arrive, they shoot Benny and Eleven realizes that these people are from the lab she was abducted into at a young age. Eleven escapes using her telekinetic powers and runs back into the woods, where she meets Will's best friends, Mike Wheeler, Dustin Henderson, and Lucas Sinclair, who had set out to search for Will on their own.