For a year now, a pandemic of a mysterious virus has been raging on Earth, one to which most of the planet's population has grown accustomed and treats lightly. A young couple, Jim and Kat, like many others, go on living an ordinary life. One day the virus mutates in an unexpected way, stripping the infected of their human appearance and provoking uncontrollable outbreaks of aggression and lust. The outbreak of the new virus catches Jim in a crowded cafe, and Kat in the subway at rush hour, and now the young couple will have to struggle to reach each other and avoid being caught by enraged fellow citizens.