Zippy Green never meant to fall in love with a girl, but when she does, her ultra-conservative father tries to send her to anti-gay camp. At the Kansas City airport, however, she hides inside a giant suitcase and sneaks onto an airplane headed not to the camp, but to Seattle, where her online love Mira lives. Halfway through the flight, the plane barrels out of control and crashes into the ground, knocking her unconscious.

When Zippy awakens, she finds that most of the passengers have vanished. She doesn’t know what’s happened, but she’s determined to find out. She begins a quest on foot toward Seattle, and along the way, she meets a teenager with a concussion, a homeless man with a heart condition, a child without a shred of bravery, and a terrier named Judy. Together the group discovers that more than two-thirds of the world's population have mysteriously disappeared. But that's only the beginning...

All Zippy wants is to find her Mira, but before she can she has to contend with two outside forces. The first is her homophobic father, who does everything in his power to keep her from the girl she loves. And the second is extinct creatures of all shapes and sizes, including living, breathing dinosaurs, which have replaced the missing population.