In the drought-ravaged wastelands of northern Shaanxi during the late Ming dynasty, border soldier Liu Chengzong awakens from a fever with two sets of memories: his own eighteen years of life, and the fragmented knowledge of a soul from four centuries in the future. The fusion leaves him restless, seeing his starving garrison, his dyed-red horse, and the crumbling Yühe Fortress through a strange double lens. The land is dying, the people are hollow, and the Ming military machine is rusted through with neglect.

As famine refugees strip the earth bare and his comrades survive on millet porridge and wild geese, Liu Chengzong grapples with a mind full of contradictions. He knows how to hunt, how to fight, and now, perhaps, how the world will turn. But knowing the future and surviving the present are two different things.

When a starving orphan named Sixteen arrives, scooped up from the refugee columns, the fragile bonds of brotherhood among the border troops begin to solidify. In a fortress where doors are left unlocked not from trust but from poverty, Liu Chengzong must decide what to do with the dangerous knowledge burning in his skull, as the first sparks of rebellion begin to flicker across the land.