Shen Qiu Ping / Tian Liu --- Chen Yao
Shen Qiu Ping --- Chen Yao
The female instructor is a complex and contradictory character. She has both loyalty to her country and nation and desires for herself and her loved ones. She possesses a passion for the revolutionary cause but also yearns for a happy life. In the end, she chooses to betray her comrades and organization by betraying Chen Ke Hai to protect Fang Li. She pays the price for her mistakes with her own life and leaves behind regrets for her love.
Li Tang --- Meng A Sai
Li Tang is a carefree, innocent, opportunistic, and witty military intelligence agent. He has no desire to get involved in internal struggles within the military intelligence organization and only wants to focus on completing his missions. Therefore, he has never doubted Chen Ke Hai. However, his own identity is also very complex. He fools everyone with his foolishness and helps Chen Ke Hai complete the mission. It turns out that Li Tang is also our undercover agent, but he is incredibly skilled at disguises, making it difficult for anyone to detect his true motives.
Chen Ke Hai --- Gao Zhi Ting
Chen Ke Hai is the ace agent within the military intelligence organization. He initially went to the frontline of the anti-Japanese resistance. After being injured, he was secretly saved by Lao Duan and recruited into the underground party. Two years later, he was assigned by the organization to return to Shanghai, and with Fang Li's recommendation, he joined Unit 76. However, Fang Li doesn't trust Chen Ke Hai and constantly tests him in various ways. Despite being a novice trainee in the military intelligence, Chen Ke Hai can easily see that Instructor Jin's gun is empty and can discern Shen Qiu Ping's true intentions.
Fang Li --- Wang Sen
The director, driven by immediate gains and ruthless in his actions. In his childhood, he was penniless and had no one to rely on. If it weren't for Chen Ke Hai's help, Fang Li would have been homeless. He always wanted to repay Chen Ke Hai's kindness with all his might, but he was too sensitive and only wanted to surpass Chen Ke Hai at all costs, forgetting his youthful self who valued loyalty and righteousness. In the end, Fang Li met a tragic death when Chen Ke Hai shot him, resulting in a grim conclusion.
Luo Bing --- Zhang Yue
The patriotic female agent is a gentle yet strong character. She doesn't possess the complexity and contradictions of Shen Qiu Ping, nor the coldness and decisiveness of Tian Liu. She has a love for Chen Ke Hai and sympathy for Fang Li. She chooses Chen Ke Hai between the two men, the Communist Party between the two beliefs, and the life of an agent between the two identities. In the end, she chooses to part ways with Chen Ke Hai and ventures into a new battlefield to continue her mission.
Chen Bin --- Jiang Xue Ming
Chen Bin is deeply cunning, exceptionally clever, and skilled in disguise. He can always spot Chen Ke Hai's weaknesses at a glance. As a result, he keeps a close eye on Chen Ke Hai and even sends Li Tang to test him. When it comes to strategy, he is undoubtedly more brilliant than Fang Li. However, he also chose the wrong side from the beginning, infiltrating the military intelligence as a spy for the Japanese. In the end, Chen Bin engages in a final showdown with Chen Ke Hai.
