Xiao Dao informs Yun Hongqi that Qu Wenzhi’s betrayal was exposed in the newspaper and the Rat Brothers immediately recognized him. Rat witnessed Qu Wenzhi spending the night at Li Miaohan’s house. Yun Hongqi is shocked and criticizes Li Miaohan’s lack of discretion. Xiao Dao remarks that people can be deceptive, which explains Li Miaohan’s popularity. Yun Hongqi asks Xiao Dao to check on Xiao Huang, feeling responsible for his troubles. He believes the military statistics bureau is investigating Xiao Huang to pressure him. Yun Hongqi advises Xiao Dao to warn Xiao Huang to lay low, as some money is not worth the risk.
However, Wen Yeming stops them and scolds them for eavesdropping, telling them to stay there until they develop supernatural hearing. Yun Hongshen adds that since their eyesight is so good, they will each do 100 push-ups tonight. During the meeting, Ke Jingping states that the key is to find the cipher. Deputy Station Chief Zhu orders Yun Hongshen to hand over the codebook. Yun Hongshen claims he cannot, saying he forgot where he put it. The deputy station chief demands he write it from memory, as he is capable of doing so.
Yun Hongshen claims he forgot after sleeping. Deputy Station Chief Zhu is about to lose his temper, but Ke Jingping intervenes and orders Wen Yeming to confine Yun Hongshen. Wen Yeming reports to Ke Jingping their suspicion about Shunde Company and the need to investigate it. Ke Jingping informs Wen Yeming about potential issues at the training base. Wen Yeming suggests investigating all personnel at the base, and Ke Jingping assigns her the task. Wen Yeming asks if confining Yun Hongshen is a ploy to send him to the base, which Ke Jingping confirms. Ji Fang, a spy for the Japanese, appears nervous when Yun Hongshen questions him.
At the base, they observe instructor Zhang Hua passionately training recruits. During dinner, they plan to take action that night. They notice something is amiss with Zhang Hua. Wen Yeming sends a telegram to Ke Jingping, but the Japanese intercept it. Yun Hongqi takes Milan home, where she secretly investigates Yun Hongshen. At the base, Instructor Teng spars with Yun Hongshen and, unable to defeat him, resorts to using a dagger. Yun Hongshen counters and stabs Teng in the leg. Teng dies, and they discover the dagger was poisoned. Yun Hongshen realizes Zhang Hua is responsible.