The rampant spread of a virus has turned most humans into grotesque beings called "the Rotten." Amidst the ruin, Seonho leads a small group of survivors and protects his companion Haesoo, who is bullied for being weak and timid. Seonho’s group is thrilled to meet more survivors with a large stockpile of supplies—until they realize that this new group is shockingly barbaric and cruel. By far the most twisted is their leader Won, who has his dangerous eyes on Seonho. Determined to shield Haesoo, Seonho makes a deal with Won... but will any of them make it out alive?