On an ordinary day, Gerry Lane and his family find their quiet drive interrupted by urban gridlock. An ex-United Nations investigator, Lane senses that this is no ordinary traffic jam. As police helicopters buzz the sky and motorcycle cops careen wildly below, the city erupts into chaos. Something is causing hordes of people to viciously attack each other - a lethal virus that is spread through a single bite, turning healthy humans into something unrecognizable, unthinking and feral. Neighbor turns on neighbor; a helpful stranger suddenly becomes a dangerous enemy. The origins of the virus are unknown, and the number of infected grows exponentially larger each day, quickly becoming a global pandemic. As the infected overwhelm the world's armies and rapidly topple its governments, Lane is forced to return to his dangerous former life to insure the safety of his family, leading a desperate worldwide search for the source of the epidemic and a means to stop its relentless spread.