The Demogorgon, a predatory creature from the parallel dimension known as the Upside Down, entered Hawkins, Indiana in November 1983. This event occurred when Eleven, a child test subject from Hawkins National Laboratory with psychokinetic abilities, made transdimensional contact with the Demogorgon. This contact inadvertently opened a gate between dimensions at the lab, allowing the Demogorgon to set foot in Hawkins and begin its reign of terror.