When Gu Yunzheng, an associate professor of neurosurgery, was performing a medical aid mission in Lakaya, he met Su Weian, a "deserter" who had given up medicine to do business. The two went from being happy enemies to falling in love with each other. He gradually discovered that all her abnormal behaviors were due to her carrying the Huntington's disease gene. His lover made him empathize with the sadness and despair of the 30,000 Huntington's patients and their families in the country who had no cure. Gu Yunzheng decided to give up his bright future and devote his life to the research of curing this rare disease, and chisel out a light in the darkness with his lover.