The largest storm to hit Oklahoma in more than half a century is brewing, and it promises to drop multiple twisters into Tornado Alley. It's the storm that two rival groups of scientists-Jo Harding and her band of brash university students, and corporate-sponsored Dr. Jonas Miller and his sleek, crack cadre with their state-of-the-art research vans-have been waiting for to earn their place in meteorological history. Each team wants to be the first to launch their own equipment pack inside a twister to transmit valuable scientific data about tornado behavior. But to do so, they must put themselves directly in the path of the marauding monster-and stay always just ahead of the swirling twister, anticipating its every move. Adding to the charged atmosphere, Jo's soon-to-be-ex-husband, meteorologist Bill Harding, reluctantly joins Jo and his old crew for this last, epic chase.