While working for a humane organization in Kenya, Chloe Freestaff, a twentysomething magazine writer, finds evidence of a mass murder in a remote grassland. Infuriated by the senseless slaughter, she determines to find the perpetrators. Back in the U.S., she learns of a secret group called Population Office for the World, whose five members, all scientists, believe that the only way to save the future earth from human-caused destruction is by reducing the world's population. When the entire population of San Ignacio, a small California city, is wiped out by an aerosolized toxin, Chloe is sure this group is responsible. She makes friends with San Ignacio's only survivor, Earl Schuller, an elderly man with COPD and throat cancer. Sharing her plan with no one but him, she tracks down the leaders of the Population Office, but is captured and, in order to survive, must agree to write an article for them. The article, intended to convince the world to take population control seriously, will announce the date of the next strike but not its location-which she learns will be Phoenix, Arizona. As disturbing as the strike itself is Chloe's discovery that the toxin is generated by using E. coli bacteria that, unlike the usual attenuated laboratory bacteria, can potentially share their genes with the E. coli that inhabit the bowels of every person on earth and render them capable of spreading the toxin. Several days before her article's due date, Chloe escapes the lab compound with a bottle containing mature bacterial cultures. The group attempts to recapture her, but with Earl's assistance she escapes. Chloe directs FBI investigators to the remote airstrip where the group has gathered. When the group members attempt an escape, their toxin-laden plane is shot down. With the Population Office no longer a threat, and the spread of the bacterial toxin controlled, Chloe becomes the spokesperson for an organization with goals similar to those of the Population Office, but pursued in a humane, peaceful way.
