An unexpected inspector drops by a lavish party of a notable family in order to investigate the suicide of a pregnant girl. This breaks the joy and peace of the party which is meant to celebrate a couple's engagement. Everyone claims that they do not know the girl. However, the inspector does find something suspicious there with the help of a diary and a photo. An astonishing truth is gradually revealed: six of the noble family members are closely related to the girl's death.

Lin Xiang and Lan Fang, who is pretending to be his wife, are sent to Shanghai to rebuild the underground headquarters and help liberate China from the Japanese invaders.