In this terrifying thriller, a devastating pandemic ravages the world and the United States is in its fourth year of lockdown. Infected Americans are ripped from their homes and forced into quarantine camps known as Q-Zones, from which there is no escape, as a few brave souls fight back against the forces of oppression. Amid this dystopian landscape, a fearless courier, Nico (KJ Apa), who's immune to the deadly pathogen, finds hope and love with Sara (Sofia Carson), though her lockdown prohibits them from physical contact. When Sara is believed to have become infected, Nico races desperately across the barren streets of Los Angeles in search of the only thing that can save her from imprisonment ... or worse.