The Ming Dynasty Crown Prince Zhu Xiaotian (played by Li William) has a preference for woodworking and dreams of becoming a top-notch carpenter like Lu Ban. In order to achieve this wish, he secretly leaves the palace to search for the lost woodcraft secrets of Lu Ban - the "Lu Ban Book". According to legend, possessing this book could result in minor misfortunes such as immorality or foolishness, or severe consequences like losing limbs or even one's life; either way, it brings bad luck to oneself or misfortune to one's family. Therefore, this book is also called "Que Yi Men" (The Missing Skill).
Zhu Xiaotian encounters Tang Xiaodie (played by Huang Yi) on his journey to find the book. Together, they find Tang Xiaodie's master brother, the inheritor of the "Lu Family" woodcraft tradition, Jiangnange, who has been confined by the owner of Qian Cabinet (played by Fang Xiting) and a bartender (played by Li Yu). Before his death, Jiangnange reveals a secret to the two of them.