Chen Shan, who has practiced martial arts for many years, came to the county town to find his older sister Chen Xiu, and discovered that his sister held key evidence of a construction site's shoddy work causing casualties, and was being coerced and threatened by real estate group evil forces. Relying on his martial arts skills, Chen Shan became a security captain, teamed up with Shen Qingshuang to collect evidence, and was not afraid of the other party's coercion, temptation, and malicious framing. After going through numerous crises, protecting witnesses, and finding complete criminal evidence, he brought unlawful elements like Lu Hongfa to justice, upheld justice, and protected those around him.