The third prince of Great Jin, Baili Jing, is conferred as the Prince of You and dispatched to the desolate frontier county of Youzhou. Accidentally binding with the "Heart of the City Lord" infrastructure system, his life is bound to the city—if the city falls, the person dies. Facing crumbling city walls, impoverished livelihoods, and border threats, the young vassal king goes from initial panic to relying on the system and ingenious ideas to build his manor, reclaim wasteland, boost commerce, and guard the northern frontier. Step by step, he transforms the bitter and cold Youzhou into a prosperous paradise.