Doomsday queen Gu Zhaoning is reborn as the bullied legitimate daughter of the general's mansion. As soon as she wakes up, she sees through her stepmother's poisoning scheme, punishes wicked servants in reverse, exposes her stepsister's white-lotus disguise, wins her grandmother's trust with superb medical skills, takes charge of household management to clean up the mansion's deficits, and decisively repels an unscrupulous marriage proposal. She forms an alliance with Prince Jing Pei Xuange to thoroughly investigate the military grain case, goes to the borderlands together to relieve the besieged city's plight, uses doomsday supplies and strategy with three hundred troops to crush three thousand enemy cavalry and ferret out the traitor within the army. After returning to the capital, the two join forces to crush Prince Yong's rebellious plot, finally tying the knot, securing the country and household, and ultimately achieving fulfillment.