When an estranged couple come to the aid of their dying daughter, the experience sends them spiraling into spiritual crisis and brutal heartbreak.

A cash strapped feminist filmmaker secretly takes a job directing a porn film in order to get her thesis film, "Feminism For Dummies" out of the lab. Soon, her own slumbering sexuality is awakened in surprising ways. This arouses the suspicion of her politically correct husband, Hugh, and leads to a madcap finale of mistaken identity that threatens to upend Gillian's best laid plans.

故事讲述的是一群纽约剧院演员，来到荒郊野外的月亮湖营地，准备过上一段修身养性、发现自我的日子。却不想，此处乃邪恶之地，由月亮的潮汐运动的作用在此聚集成强大的力量，从而引起人类头脑的变异，人们会变得疯狂、甚至于完全失控！而这13个成员中就有一个已经被邪恶的月亮所控制，他开始悄悄的在背地里疯狂的杀人，他是谁呢？