One night, several deer hurl themselves unexpectedly against the electric fence of a farm. Seeing deep signs of biting on the animals' bodies, the farm owners realize that a predator is roaming about the neighboring woods. Having determined to hunt it down, the farmer and his family penetrate deep into the surrounding forest. They look with bewilderment at the dying environment ravaged by a mysterious evil force. As the sun slowly sinks away, howling resounds through the forest. The hunters have become prey...