What seems to Mike Evans like a boring dinosaur dig in China turns suddenly dangerous when he finds evidence of a live dinosaur in the neighborhood--and he and his friend Shannon run into a villain in a skull mask called Mr. Bones who is controlling both a feathered dino, and a fierce carnivore.

Michael Evans and his paleontologist father have been invited by the mysterious time-traveling Shannon to visit the complex built around an underwater portal to the Jurassic period, but Mike uncovers a plot to steal one of the dinosaurs--and then Shannon and her trouble-making brother Jeff disappear through the portal.

His father and everybody else at the museum in New York is excited over the dinosaur eggs that Mike Evans found in Montana--the trouble is they are hatching and Mike will need the help of his mysterious and time-traveling friend Shannon to capture them before they wreck the museum.