Border forest police officer Ali and his teammate Li Derui are on a routine patrol in the mountainous border region. At the same time, university professor Li Rui and her student Qiao'er, who are there to study the distribution of wildlife, get lost in the forest and send out a distress signal. By a twist of fate, they fall into the hands of a group of poachers; just as a Tibetan brown bear relentlessly pursues them, turning the situation increasingly perilous.
