Used - The Ghost Of Fossil Glen

Allie Nichols is being pursued by a ghost. Her friend Karen calls Allie a liar and doesn't want to hear "stuff like that." But her old pal, Dub, listens eagerly as Allie tells him about the voice that guides her down a steep cliff side, the girl she imagines who begs, "Help me," and a terrible nightmare in which that girl falls to her death. Who is that girl? Is she the ghost? And what does the ghost want from Allie?