In the middle of the Indian Ocean, a NUMA research vessel is taking water samples at sunset, when a crew member spots a sheen of black oil ahead of them. But it is not oil. Like a horde of army ants, a swarm of black particles suddenly attacks the ship, killing everyone aboard, while the ship itself goes up in flames.

A few hours later, Kurt Austin and Joe Zavala are on their way to the Indian Ocean. What they will find there on the smoldering hulk of the ship will eventually lead them to the discovery of the most audacious scheme they have ever known: a plan to permanently alter the weather on a global scale. It will kill millions . . . and it has already begun.