It's 1988, and nothing has happened in Hawkins since El and her adoptive family moved back. Or at least that's what El thinks. Things take a drastic turn when El finds herself back in the Hawkins National Laboratory, where experiments run are far more dangerous than before and even more dangerous monsters are on the loose. With the portal to the upside down no longer in effect, and her powers coming back to her in small intervals, El finds that it's not just her who is once more a prisoner at the Laboratory but her friends as well.