After an experimental drug trial goes horribly wrong, the surviving test subjects have to fight off sleep, and each other, to stay alive.

一对感情疏离的姐妹终于重聚，姐姐艾莉（阿丽莎·萨瑟兰 Alyssa Sutherland 饰）意外被恶魔附体，妹妹贝丝（莉莉·沙利文 Lily Sullivan 饰）和她的外甥女们为生存展开反击。