Shen An is reborn in another world and awakens the Sword Immortal System, becoming a low-ranking constable in Taoyuan County. With one sword strike, he slays evil spirits; with two, he destroys demon kings. He's equally skilled at earning money and protecting his wife. Thus begins his journey toward becoming an invincible Sword Immortal. But who could have guessed that his gentle and beautiful wife, Lan Caier, is actually a supreme dragon demon? With an adorable little black snake and a greedy little white fox by her side, trouble follows wherever they go. Taoists come looking for trouble, demonic cultivators cause chaos, and evil gods wreak havoc. All he can do is settle everything with a single sword strike.