Fifteen-year-old Kenna has a problem. On her class field trip to Hawaii Volcanoes National Park, her presence makes a crack open in the earth, nearly roasting her classmates alive with lava. Perhaps defying her parents' orders not to attend the trip was a bad idea.

When sixteen-year-old Janelle, now Tempest High Leader, meets her, she knows her Hawaii vacation is over. For the first time, she's met another kind of walking disaster. But before she can get to the bottom of why, Kenna disappears.

Now if Janelle can't track her down, Kenna's secret could spell the end of civilization, and the death of Gary and everyone else she loves.