Twenty years ago at college, Martin, Paul, Jane, and Gwen were members of the GLUE Club - the Gaffney Legendary Urban Explorers - run by the charismatic Tom. Now, following his mysterious death, they agree to meet up again and undertake one final exploration to honour his name. Aside from Paul who never left, none of them have been back to Gaffney since and the reunion is awkward, re-opening old wounds. As they begin to explore the long-abandoned Pocock Factory, it seems they might be intruding on something better left alone. As they succumb to the spirits in the darkness, it quickly becomes a battle to see who will survive the night...