He Zisheng: The male protagonist, who was conscripted into the army after failing the college entrance examination, has a cheerful personality, refuses to admit defeat, and has the courage to innovate. He later grows into the captain of the Jianglin City Fire Brigade. Yu Manjiang: The fire police officer who recruited He Zisheng to join the army. He is rough and fine, daring to fight and fight hard. He used to be the political commissar of Jianglin City Fire Brigade. Yu Lisa: Yu Manjiang's son, a young and active fire officer. Ren Kaishan: also known as Ren Lao, Yu Manjiang's master, an authority on firefighting expertise, and the first generation of firefighters after the founding of the People's Republic of China.

Sun Mingjie: He joined the army in the same year as He Zisheng. He was steady and scheming, and competed with He Zisheng for positions many times. Fang Ping: He joined the army a year earlier than He Zisheng. He was kind and easy-going. He was discharged from the army after failing in the military academy and later became a corporate executive. Feng Yuanyuan: A beautiful, thoughtful modern intellectual woman, married to He Zisheng, and has a daughter, He Jiaer. Gao Xin: After graduating from university, she joined the army. She is a down-to-earth and rational female fire police officer who is engaged in professional and technical work in fire prevention.

Zhao Fang: Yu Manjiang's wife, pungent and enthusiastic. Jiang Yina: Sun Mingjie's wife, a hospital nurse, has an arrogant personality. Jin Mei: A female fire police officer engaged in logistics equipment management, and later changed jobs.