At the end of the 1970s, Li Ping, a female worker at a cigarette factory in a certain city and harboring dreams of marriage, inserted a small note into a cigarette box. As she was waiting, officer Wu Tianliang appeared before her, and she followed this man to his military post, beginning their married life. Married life was different from what she had imagined, but she became close friends with her husband's subordinate, Wang Xiaomao. Soon, both Wu Tianliang and Xiaomao were transferred to work on the construction of the Qinghai-Tibet Railway under the Ministry of Railways. Since Wu Tianliang had shifted all his energy to his work, Li Ping's life became monotonous and dull. During a solo trip home to visit family, Li Ping decided to see Wang Xiaomao. Upon meeting again, they were reluctant to part ways, and Li Ping asked Wu Tianliang for a divorce. Not long after, Li Ping remarried Wang Xiaomao, and a daughter was born, leading to a happy and harmonious life. Xiaomao borrowed money from all sides, raising funds to buy a car and becoming a taxi driver. Unfortunately, good times didn't last long, as Xiaomao was killed while fighting off bandits. Wu Tianliang's second wife also died at the Qinghai-Tibet Railway construction site. The two met again, each bringing their children, causing Li Ping to deeply reflect on her concept of happiness.