From the first chapter, the plot of the first season of Stranger Things was articulated around two great subjects: the disappearance of Will (Noah Schnapp) after seeing a strange creature, and the appearance of a mysterious girl called Eleven (or Eleven , Millie Bobby Brown).
The two realities came together from the beginning, since Will's friends - Mike (Finn Wolfhard), Dustin (Gaten Matarazzo) and Lucas (Caleb McLaughlin) - started looking for their friend on their own, apart from the police investigation by Hopper (David Harbor). And precisely Mike welcomes Eleven into his house, secretly.
By then, the girl had already shown that she had some kind of power, and seeing a picture of Will is scared, which makes Dustin and Lucas suspicious, but not Mike. Together the four, continue looking for their friend.
Disappearance of Will and appearance of Eleven
As the mystery grows, for example with the famous disappearance of Barb, both the investigation of Agent Hooper and the children goes to the same point: the Hawkins National Laboratory. The policeman, for his inquiries. The children, because Eleven begins to open up and explains that Will is in what they will later call "the world upside down".
Joyce, the mother of the child played by Winona Ryder, begins to go crazy but manages to establish contact with her son through the Christmas lights. The intrigue also extends to Nancy (sister of Mike, played by Natalia Dyer), who begins to collaborate with Jonathan (brother of Will, played by Charlie Heaton) to find both Barb and the lost child.
Then, on the one hand the children begin to ask about the possibility of the existence of parallel dimensions, and on the other Nancy finds a portal to this other dimension when she goes through the forest with Jonathan in search of Barb. The young woman is about to die trapped by the strange creature that lives in that place, but manages to save herself and return to the normal world.
Eleven discover his powers
After a small break in the children's unit, and after Eleven demonstrates her powers twice, the men who chase the girl plant themselves in Mike's house to catch her, but they all manage to flee in time.
At the same time, Hooper and Joyce discover, together with Nancy and Jonathan, that Eleven was the one that mistakenly opened the portal to another dimension that had allowed to appear to the strange beast, the Demogorgon. The girl confesses it, but offers to help them, and travels the world upside down to find Will, who is in danger because the creature has found him.
