In the quiet town of Hawkins, Indiana, 1983, life usually moves slowly. Kids ride bikes after school, parents work at the Hawkins National Laboratory, and nothing strange happens — until one stormy night.
Twelve-year-old Will Byers is returning home from a long Dungeons & Dragons session with his friends Mike Wheeler, Lucas Sinclair, and Dustin Henderson. As he bikes through Mirkwood Road, he senses something chasing him. His dog barks, lights flicker, and something unseen approaches. Will runs into his home, but the creature follows. In a moment of panic, Will disappears — leaving only his bicycle behind.
Meanwhile, inside the heavily guarded Hawkins Lab, something horrifying has broken free from a sealed chamber. Scientists panic as alarms scream through the halls.
The next morning, Will's mother Joyce reports him missing. Police Chief Jim Hopper, a tired man haunted by his past, begins investigating — but he thinks it's just a normal missing-kid case. Mike and his friends refuse to sit still and secretly plan their own search.
Later that night, during a thunderstorm, a mysterious shaved-head girl wearing a hospital gown appears at a local diner. She doesn't speak. The only clue she offers is the tattoo on her arm: "011."
The story of Hawkins' first mystery has begun.