Nine-tailed fox Tu Shan Yao, to repair the crumbling barrier and raise her clan, brings her four-year-old son Tu Shan Xiao Bao to find Huo Yun Zheng, a man with pure yang merit. The mother and son board a green-skinned train, outwit human traffickers, and save money to settle down by gathering medicinal herbs and trading on the black market along the way. As the chief rescue captain, Huo Yun Zheng feels protective of the frail, mysterious mother and son, so they register their marriage and move in together. A group of spirits come to seek refuge; Xiao Bao, the clever girl Shen Si Qing, and the cat demon Miao Miao help them earn a living. As the couple work through their differences and gradually fall in love, they join forces to repel fierce beasts, the spirits settle stably at the brick kiln factory, and the two live a peaceful life hand in hand.