In Shanghai in 1941, Fang Jiashu, a Communist Party member who was lurking at No. 76, the headquarters of Wang puppet spies, was in danger of being exposed. At this time, his Tongyangxi as a teenager and Tao Yuling, who was also an underground worker of our party, invaded his life with two children, and in order to protect Fang Jiashu's latent identity, they began to pretend to be a family with him. On the other hand, Fang Jiashu also holds the status of a military intelligence agent and must navigate various relationships. Even in such a complex situation, Fang Jiashu cleverly obtained more intelligence and benefits for our party.