Davy Ross was staying with his grandmother and just about to celebrate his eleventh birthday when he received word that his parents, paleontologists for the Natural History Museum, were missing and believed dead on an expedition in Africa. A few days later, a trunk containing his parent's personal affects arrives and in that trunk, Davy finds what appears to be some kind of egg. Assuming it is one of the many fossils his parents are always bringing back from their digs, Davy sets it on a shelf along with his other dinosaur memorabilia. During the night, the egg hatches. As the story unfolds, readers experience an adventure about an unusual friendship in which a young boy, whose paleontologist parents are missing, who finds himself in possession of something long believed to be extinct.