While escaping from a locked room, Pei Zhiyu and Lu Chuan transmigrated into characters from a book. Pei Zhiyu's husband, Xiao Run, turned out to be a cruel crown prince. Through a coded message from Xiao Run, the two confirmed each other's transmigrators and decided to cooperate to change their fate. Pei Zhiyu obtained the answer book, learning that finding a third transmigrator would allow her to return to the modern world. She then began testing those around her in her search.