Jiang Yao takes her sister's place for a nominal engagement, marrying Lu Qianhan, who has been left with physical and psychological scars from an accident. Upon entering the Lu family, the two strictly maintain the superficial form of a married couple, remaining guarded against each other, and their daily interactions are filled with playful tests and probing. As they spend days and nights together, Jiang Yao's open and lively personality gradually melts away the defenses of Lu Qianhan's closed heart. Hand in hand, they peel back the layers to unravel the mystery behind the past accident, shedding their disguises beneath this besieged fortress-like marriage shell to see the real each other, reaping bidirectional understanding and tenderness, and jointly walking towards a stable life belonging to them.