Five women participate in a hiking retreat but only four come out the other side. Federal agents Aaron Falk and Carmen Cooper head into the mountains hoping to find their informant still alive.

Five women participate in a hiking retreat but only four come out the other side. Federal agents Aaron Falk and Carmen Cooper head into the mountains hoping to find their informant still alive.

影片围绕着心理学家皮特与他被“鬼混”侵扰的病人之间展开，随着病情研究的深入，隐藏在恐惧背后的可怕事件也将渐渐浮出水面。