On the bank of the Yarlung Zangbo River on the Qinghai-Tibet Plateau, hydropower engineer Chen Yuan met Dolma, a Tibetan female technician, because of his work. He told her about the technical problems, and she told him about the legend of the sacred mountain. The two lonely souls warmed to each other. Chen Yuan made a promise to take her to Namtso to watch the stars when the "Electric Sky Road" was completed. However, water suddenly surged in the power station tunnel, and Chen Yuan was swept away by the torrent in order to rescue the information, leaving no trace. When the bad news came, Zhuoma's world collapsed instantly, and a new life was quietly gestating in her belly. She chose to be strong and gave birth to her daughter alone, relying on the diary left by Chen Yuan to express her thoughts. Three years later, hydroelectric stations illuminated the plateau. One evening, Zhuoma led her daughter to pray on Barkhor Street, when a figure in ragged clothes and a vicissitudes of face blocked the way - it was Chen Yuan. It turned out that he was seriously injured and lost his memory after being washed downstream, but was rescued by herdsmen. Relying on his vague memory of Dolma and his life instinct, he trekked along the Yajiang River for three years with no language skills and no money, and finally returned after all the hardships. In the huge shock of the reunion, Zhuoma choked up and told the origin of her daughter. After the shock and severe pain, Chen Yuan felt a surge of distress and guilt in his heart. He hugged his lost love and the crystallization of his blood tightly. The setting sun gilded the reunion of the family of three with golden brilliance, and the promise they had made was realized in a more profound way: the light they guarded together has illuminated the snowy field, and each other has become a beacon that will never go out in each other's life.
