After the death of her policeman father, Xiaomai begins to look over his old journals filled with notes about the cases he investigated over the years. The mention of a purple scarf in the notes particularly catches her attention, prompting her to purchase a similar scarf from a mysterious website that claims to sell everything, as long as one can pay the price. Soon after, Xiaomai's close friend is found dead, strangled by a purple scarf. All of this awakens Xiaomai's memories of her childhood sweetheart Qiushou, whose mother was also strangled to death with a purple scarf by an unknown killer. Xiaomai and Qiushou grew up together and fell in love, but he suddenly disappeared from her life 15 years ago without a word. She begins to believe that Qiushou has returned and may be seeking revenge.
In 1969, a young Beijing student, Chen Zhen, is sent to live among the nomadic herdsmen of Inner Mongolia. Caught between the advance of civilization from the south and the nomads' traditional enemies - the marauding wolves - to the north; humans and animals, residents and invaders alike, struggle to find their true place in the world
