Shen Zhiwei, the legitimate second daughter of the Duke of Zhenguo's household, flees home in the middle of the night to escape a forced marriage imposed by powerful forces. Unexpectedly, she loses her footing while climbing over the wall and falls straight into the arms of Xiao Yanci, the Heir of Prince Jing'an! To evade the searching household guards, she forcibly pulls the aloof heir into a stone cave and conveniently takes him along on her escape. Everyone knows that the Heir of Prince Jing'an is ruthless, cold, and uninterested in women. Yet ever since meeting Shen Zhiwei, he repeatedly breaks his own rules. After marrying into the Xiao household as the heir's wife, Shen Zhiwei becomes embroiled in bitter family power struggles. Incited by Nanny Zhang, the Old Madam constantly guards against and suppresses her. Shen Zhiwei carefully protects herself at every turn, while she and Xiao Yanci gradually move from icy mutual respect to genuine trust. Together, they uncover a conspiracy of false accusations, clear their names, and resolve the grudges within the household.