Dr. Ke Lin led the medical team into the border gate to rescue refugees, and unexpectedly reunited with his brother Ke Zhengping, only to learn that his younger brother was the underground party escorting the first batch of protection targets.The two brothers cooperated tacitly and disguised their protection targets such as He Xiangning and Liu Yazi as medical volunteers to avoid being hunted by the Japanese army.

Huang Gongjie led a special agent into the border gate and used the opportunity of issuing passes to investigate fugitives. Cai Chusheng and others were almost exposed, but fortunately He Xian made a witty rescue.