A young American backpacker enlists a French couple to help him find a fabled Thailand beach where other backpackers have formed a tropical utopia.

This is the way the world ends: with a nanosecond of computer error in a Defense Department laboratory and a million casual contacts that form the links in a chain letter of death. And here is the bleak new world of the day after: a world stripped of its institutions and emptied of 99 percent of its people. A world in which a handful of panicky survivors choose sides - or are chosen. A world in which good rides on the frail shoulders of the 108-year-old...