Chris, a light-hearted person, is enjoying a visit with friends in the United States. But when he wakes up one morning, everything has changed. Something has transformed people into bloodthirsty beasts overnight. In panic, he flees the city. His hope of escaping the horror and finding normality in a different place quickly fades. Soon, it is only a matter of survival. On his escape, he meets Sarah, who seems better able to cope with the situation, and decides to join her. On their arduous journey into the unknown, both are confronted with fear, hatred, love and betrayal, and are put to a crucial test.