The never-ending monsterization crisis. Hyeon Su, consumed by monsters, tries to regain his human self. Nam Sang Won, who entered Pyeon Sang Uk's body, visits the survivors' stadium with a group of people to achieve his goal. And unlike the previous rules, they put forward an unconventional condition to provide convenience to those with symptoms. Stadiums are no longer safe spaces, and people are confused. Meanwhile, Eun Hyeok, who was reborn from the cocoon, appears in a new form... Season 3, which will mark the finale of the desperate struggle of those who are faced with a choice between the border between monsters and humans.