The sudden appearance of exotic flowers in New Haven spawns an unprecedented epidemic that threatens to destroy the city. Infected people cover themselves maniacally with lotions, creams, and rags, ranting about returning to a better world, attacking and infecting others. Paul and Lauren, a married couple, are caught between the catastrophe and their own troubled relationship. Paul has grown defeated and depressed from job frustrations and their banal existence taken its toll as she becomes more and more isolated and he descends into alcoholism. On her way out of the house to leave Paul, Lauren encounters one of the flowers and becomes infected. As her symptoms worsen, Paul's denial of Lauren's illness puts the couple in grave danger as the city is overrun with infected people, media frenzy, National Guard, protesters and a panicked populace. As the epidemic reaches a climax, Paul struggles to save both their lives.