故事发生在第二次世界大战的最后几个月，《战争之雾》告诉了受伤的美国飞行员吉恩和他的OSS特工未婚妻佩妮回到马萨诸塞州的一处偏远庄园，与佩妮的远房叔叔罗伯特住在一起的故事。在她不知情的情况下，OSS招募了吉恩来监视这个家庭和周围的社区，因为与D日入侵有关的绝密文件被盗，一名敌方内奸就在附近的某个地方，准备将这些计划移交给轴心国。

在这部电影中，一队特种部队突击队员在执行任务的过程中被一艘神秘的宇宙飞船绑架。当他们在飞船上醒来时，很快发现自己正在被一个无情的外星种族追捕。

As Alyssa and Karla try to escape from the church home that holds them captive, Karla is slaughtered by a vicious, semi-human creature. After Detective Kimball tracks down Alyssa at a rowdy biker bar, she tells Kimball that women inmates disappear every full moon, and shows him the silver bullets in her gun. Now the two must return to the halfway house to confront the priest and nuns—and the snarling, savage evil—that dwell within.