A series of Gruesome killings is shaking Herefordshire. Beth, a mother in her sixties is showing signs of early Alzheimer. Worried about her, her daughter Jess and son in law Connor, try to find a way to help her. Together they purchase an old house on Wyvern Hill so that she can move in with them and be looked after. However, her symptoms and slow loss of reality render Beth unable to realize that something has moved in with her, observing her every move and preparing in the darkness of Wyvern Hill.