Tian Liqiu (played by Xie Xian), Cai Feng (played by Feng Baobao), and Ye Yicong (played by Lin Xue) were once a feared assassin organization in the 1960s. However, the times have changed, and the three have no choice but to take off their uniforms and return to ordinary life. Entering the twilight years, who wants to be labeled as a negative asset? With a radio song "Youth Song", the three rekindled the fire in their hearts...