Following the sudden and mysterious death of their father, a brother and sister return home to their sprawling New Orleans estate and encounter their unhinged stepmother, who will stop at nothing to gain control of their inheritance.

一行人在深山裡迷了路，還得應付一群軍閥頭目及外星異形，但最後卻無人倖免。一條異變毒蛇因其幼卵受人類摧殘，決定以牙還牙，將無端闖入的人類趕盡殺絕。