Many visitors to Yellowstone National Park don't realize that the boiling hot springs and spraying geysers are caused by an underlying supervolcano. It has erupted three times in the last 2.1 million years, and it will erupt again, changing the Earth forever. Fifteen-year-old Alex is home alone when the supervolcano erupts. His town collapses into a nightmare of darkness, ash, and violence, forcing him to flee. He begins a harrowing trek in search of his parents and sister, who were visiting relatives 140 miles away. Along the way, Alex struggles through a landscape transformed by more than a foot of ash. The disaster brings out the best and worst in people desperate for food, clean water, and shelter. When an escaped convict injures Alex, he searches for a sheltered place where he can wait--to heal or to die.
