The outbreak of blue-green algae in Qijiang City, H province. Wang Wu, the vice mayor in charge of environmental protection, had to suspend his work due to overwork. Lin Hanjiang, a university professor who has made great achievements in the field of environmental protection, was appointed director of the Environmental Protection Bureau of Qijiang City.

After Lin Hanjiang took office, he found that cyanobacteria hide behind a greater environmental risk, and evidence is shown over the years from the Qijiang water sample testing report. With the support of the organization, Lin Hanjiang, without fear of power, found out the real cause of the blue-green algae outbreak. He was determined to solve not only the blue algae problem but also the water quality of the Qijiang River. However, it is easier to treat the symptoms than to cure the root causes. It is necessary to solve the environmental pollution in Qijiang from the root. It not only involves the largest industrial park in Qijiang City but also relates to the night market and boiler plant, which are both related to people's lives and livelihoods. It also faces the difficult choice of economic development and ecological environment protection.

However, Lin Hanjiang has always adhered to his original aspiration, defying difficulties, not only returning Qijiang to clean water and green mountains but also submitting a high-quality answer paper for balancing ecological protection and economic development.