Pei Ying, the female general guarding the northern frontier, has fought in wars for twelve years, only to discover that the man she loves sees her as a sharp blade for climbing the ladder of power. Heartbroken and disillusioned, she receives an imperial decree ordering her back to the capital to choose a husband. In a fit of spite, she selects Xie Heng, a notorious, dissolute marquis. Misled by rumors that she is "burly, blue-faced, tusked, and resembling Zhong Kui," Xie Heng tries every trick to break off their engagement. Yet, through their repeated clashes, he is completely won over by her boldness and sense of responsibility. From bickering rivals to partners who trust each other with their lives, they join forces to uncover military payroll corruption and a plot to restore the former dynasty, while discovering their true feelings as they overcome one crisis after another. In the end, the once-reckless marquis grows into her most steadfast shield, and together they protect the realm of Da Ning.