In the summer of 1985, these Steelworks became the lair of a severed appendage of The Mind Flayer which had been separated from Will Byers’ body the previous year and trapped within the real world after the closing of the Gate in 1984. After the Gate was reopened by the "evil Russians", the piece of the Mind Flayer reawakened where it infected hundreds of rats which were ultimately lured into the Steelworks. After ingesting fertilizer and other chemicals, the rats would explode and turn into goo which contained flesh and bones. Once it came together, it took the shape of the Mind Flayer who continued to wait for its prey. Its first thrall became Billy whose car was hit with the goo, rendering it disabled. He was then pulled in by the Mind Flayer where he would become infected. After escaping, he went to a phone booth, thereafter being transported to the Upside down where he was instructed by the Mind Flayer to build.
- The Steel Works were the location depicted in one of the first teasers leading up to Season 3’s first official trailer, depicting a large number of the scurrying rats within the basement and the caption “It’s almost feeding time”