In the mountainous region of northwest China, there is a small village called "Oil House", which is the hometown of the old man who owns the famous brand "One Drop of Fragrance", the oil rat. After nearly 20 years of absence, the oil rat returned to his hometown, the face of familiar grass and trees, he had mixed feelings, plunged into the endless memories of the past ......

Early eighties, the rural areas are in the implementation of the package production to the household. The oil mill village sheep herder oil rats out of the sheep, was forgotten by everyone, but did not share the field, the village head then wanted to send him alone to the countryside of the nursing home, but only 48 years old oil rats are not willing to accept such a life.

A chance encounter with Wang Luoban, his brother, who was an apprentice at the oil mill, has led him to a new job, which he has been working on for the past few years. Wang Luoban's father and son contracted the Elm Liang oil mill, and business was booming. The oil rat was inspired, determined to contract the village's old oil workshop. With the help of a mute villager, the oil rats renovate the dilapidated old oil mill. However, at the very beginning, the oil mill encounters the problem of having no oil seeds. The mute mom gives the oil rat the idea of borrowing oil seeds from Wang Luoban. The old oil mill's business gradually flourished.

The 15th of August comes, and the kind-hearted and simple-minded Yuren rascal pays for a theater troupe to come and sing "Two People's Stage". His generosity has been the villagers' suspicion, and some people even rumor that the oil-guzzler can get rich because he dug up the landlord's golden treasure buried under the old oil mill. Greedy, ignorant villagers despite the opposition of the oil rats, collectively to the old oil digging treasure. Seeing the oil mill, which is the result of their own hard work, destroyed, the oil rats were in pain and became very sick. At this time, the gentle and tough mute mother came into the life of the oil-rat, accompanied him through the difficult times, and together they went far away from home.

After 16 years, the oil-rat returned to Yufang village accompanied by the vice mayor. In response to the Party Central Committee's policy of western development, the city decided to take advantage of the "one drop of fragrance" brand, the establishment of a large-scale oil extraction enterprises. The oil rats, regardless of the past, suggested that the oil mill and oilseed planting base are located in the village of Yufang. The poor townspeople rejoice at this new opportunity, and they see the hope of getting rich and a better future.