The prominent Shen family of Jiangnan is suddenly charged with the grave crime of colluding with the enemy. The eldest daughter, Shen Zhaoning, takes the jade hairpin passed down through her family and brings her mother to the capital to clear her father's name. She has no idea that this towering injustice is part of a game laid out by Emperor Xiao Chengyu...
New to the capital, Shen Zhaoning makes her name through medicine, treating the people and probing hidden currents. She encounters Xiao Jingheng, the "easygoing prince" rumored to care only for poetry and painting. His calm exterior conceals a sharp mind. From testing each other to entrusting their lives to one another, she uses her medical knowledge to help him resolve the border crisis, while he uses his influence to shield her from the dangers of court. With the jade hairpin as their token, affection quietly blossoms.
The Crown Prince's attempts to win them over, misunderstandings with noblewomen, and the emperor's efforts to keep the balance of power draw the pair into the heart of the maelstrom. As the secrets of the canal transport system, the war in the northwest, and the succession struggle are gradually revealed, Shen Zhaoning finally learns the truth: her father's false accusation was bait, the prince's easygoing ways were a disguise, and the hairpin in her hand binds not only two hearts, but also the fate of the Great Jing realm.
She heals the world with a compassionate heart, while he brings peace to the realm with his schemes. From the rainy lanes of Jiangnan to the palaces of the Forbidden City, they break free of the game of power and hold fast to their sincere hearts. When the dust finally settles, the emperor's words, "Sanlang was never an idle prince," reveal the painstaking efforts of half a lifetime and illuminate the vast realm they will protect together.
