During a mission to guard a primeval forest, a female ranger met two survivors, a father and son, who lived a "post-apocalyptic" wilderness life. The father and son's beliefs seemed to be unique, and their relationship with nature was subtle and mysterious. The ranger was full of doubts about the father and son's life experience, but when their cabin in the forest was attacked by a mysterious creature at night, she suddenly realized that in this wild wilderness, there were even more terrible dangers...