After Maureen Coleman is diagnosed with early onset Alzheimer's, her children bring her to live at SummerHome. As her condition deteriorates, siblings Sean Spencer and Meghan Coleman are unsure if they have made the correct decision. They grow concerned when their mother claims to see the ghost of her dead husband, and a series of tragic, unexplained events impact the community. Now, with the residents of SummerHome believing their complex is haunted, the world-famous Para-Hunters come in to investigate. The ghost hunters soon learn this isn't a typical haunting. Because slinking through the shadows is an evil, unleashed from underneath the Mound nearly 300 years ago, and it doesn't want to go back.