Five years ago: Sky’s father fled their underground compound to go topside, to a land ruled by dinosaurs. Before leaving, he hid instructions on how to complete his mysterious mission if he were ever to fail.

Last Week: Sky stumbled upon the clues her father had left behind: a memory card, a map pointing to Lake Michigan, and a message telling her the fate of the world depends on getting there. So she and her best friend, Shawn, broke out of North Compound, following in her father’s footsteps.

Today: After narrowly escaping both dinosaurs that want to eat her and marines sent to stop her—and making some unexpected new allies along the way—Sky and her friends have finally made it to Lake Michigan. They discover a secret lab hidden in the water that is home to scientists who have actually been helping the dinosaurs. With their aid, Sky learns the truth about her father’s mission. And that he was right all along . . .

Tomorrow: It will be up to Sky and her friends to save the world from the very people who had sworn to protect it.