The story starts during the 80s, in the fictional town of
Hawkins, Indiana, when a boy named Will Byers
disappears, a fact that uncovers the strange events that
take place in the area, the product of a series of
experiments carried out by the government in a nearby
scientific laboratory. In addition, disturbing supernatural
forces and a very strange girl appear in the city. She,
along with Will's friends, will look after him, without
imagining what they will have to face to find him.
Inadvertently, they created a portal to an alternative
dimension called "Upside Down" ("The Other Side"). The
influence of Upside Down begins to affect the unknown
residents of Hawkins in a dire way.