Ash, a top demon hunter, grew weary of killing and decided to live incognito as an ordinary store clerk in Gray Rhino Town. However, when sinister red-bottled drinks from Carmine Corporation flowed into the town, residents began to mutate and turn bloodthirsty, one after another. The town was sealed off, a crisis erupted, and Sheriff Emily sought Ash's help. He took up his weapons once more to investigate the truth, only to discover that the disaster was orchestrated by James, an old enemy from his past. James intended to use Ash's blood to create a bio-engineered army, thus initiating a life-or-death confrontation.