"Fifteen years ago, Qin Man, a former Dragon Unit agent weary of violence, retired to run a barbecue stall in Jiangcheng. When her daughter faces bullying, Qin Man intervenes—drawing the wrath of the Zhao Corporation. After her daughter is kidnapped in retaliation, Qin Man joins forces with Inspector Chen Wenchang to rescue her and uncover a criminal conspiracy. Reassuming her codename ""Nightingale,"" she rejoins the Dragon Unit to purge corrupt forces and dismantle the syndicate. After saving her daughter and restoring justice, she resigns once more, choosing a quiet life with her child."
