A young couple in Taiwan, Jim and Kat, start their day like any other, but their normalcy is shattered when a viral outbreak quickly spreads across the city. This virus, called Alvin, turns infected individuals into violent, sadistic killers with an uncontrollable desire to inflict pain and suffering. As chaos erupts, the once bustling city transforms into a nightmarish battleground, with the infected attacking anyone in their path. Jim and Kat become separated amidst the pandemonium, each struggling to navigate their own treacherous journey. They must fend off not only the infected but also the uninfected who have given in to primal instincts of survival, showing that the line between humanity and monstrosity is thin.

As the world descends further into madness, Jim searches desperately for Kat, encountering grotesque horrors and moral dilemmas at every turn. The city’s infrastructure collapses under the weight of terror and violence, making the search for safety increasingly hopeless. Meanwhile, Kat faces her own perils, finding refuge with others who might not be trustworthy allies. Through harrowing experiences and relentless trials, both Jim and Kat are pushed to their physical and emotional limits. Their love and hope for reunion drive them forward, but the rapidly disintegrating reality around them poses incessant threats that could shatter their chances of survival and sanity.