Modern-day Zhang Dajian accidentally travels back to ancient times, only to face the threat of starving to death during a harsh winter in a world torn apart by chaos. His sister-in-law, Lin Wanru, arrives with her younger twin sisters from her maiden family, seeking refuge. With the family driven to desperation, they unexpectedly activate the Home Protection System. By protecting their family and neighbors and building a safe, stable home, they can exchange protection points for survival supplies and extraordinary abilities. From then on, Zhang Dajian uses the system to turn protection points into tangible resources. He protects his sister-in-law, looks after her two younger twin sisters, rescues women from a neighboring village who have fallen into desperate circumstances, tames packs of wolves deep in the mountains, and brings ruthless bandits under control. In this brutal era where people will devour one another to survive, he carves out a path to survival through sheer force of will.