For fourteen-year-old Callie, life is perfect. She can drive a Humvee, take anything she wants from stores, play with explosives, and keep library books forever. She can spend hours watching movies with the other kids in the clan or just tinkering with her machines. So what if there are only nineteen people left on earth? The Fixer virus was fourteen whole years ago and it’s not like it was the end of the world or anything.

But then Fixer returns, leaving the only remaining adult in a coma. To save her clan, Callie must lead three friends on a desperate quest across the wilds of the United States. If Callie can cross rivers with collapsed bridges, survive landslides, escape wolves and bears and giant pythons and tiny frogs, make it to the lab where Fixer was created, recover the antidote, and race back home before time runs out, she saves the world. If she fails, the last little flame of humanity gets snuffed out forever.

But, hey, no pressure.