在系列终章中，幸存者们将面对蒙面陌生人的新威胁。随着秘密浮出水面，现实与危险的界限逐渐模糊，他们的生存之战也愈发凶险。
真人真事改编，叙述小朗诺迪佛宣称屋裡的声音驱使他拿起杀伤力强大的猎枪，趁家人熟睡时将他们击毙。
Carla (25) is a lonely young woman who spends her life uploading videos to social media with the dream of becoming a famous influencer. When she discovers that a malevolent presence inhabits her home, Carla becomes obsessed with documenting the paranormal events, which generates the followers she always desired. However, as her fame increases, so does the evil force that seeks to destroy her.
在父母过世后，Lucas（奥古斯特马图洛饰）是由酒鬼哥哥Tom（迈克尔C曼宁饰）一手养大的。Lucas被同侪霸凌，于是他和树林中的怪物成了朋友，发展出了危险的关系。莉比贝拉（LibeBarer）饰演Anna，一位来自外地的女孩，她和Tom交往，并对Lucas非常关心。丹艾迪亚（Dan Hedaya）饰演警长，他曾和Tom与Lucas已过世的妈妈有过一段情，所以觉得自己有责任要照顾这对孤儿兄弟。
法庭心理学家Sally Rowe被警方委派裁定是否有足够的证据以谋杀罪指控17岁的Alex，其被控告用枪射杀了同学Nigel。因为没有实物证据，案件的侦探备受来自有权势的Alex的父亲欲使监控流产的压力。深究 Alex和Nigel奇怪的共生契约，Rowe发现虽人已死，但Nigel的精神对Alex的影响绝没有减小。
Two children wake up in the middle of the night to find their father is missing, and all the windows and doors in their home have vanished.
