65 million years ago, a Tyrannosaurus Rex pup is separated from his parents and his clan. In order to find them, he must brave erupting volcanoes, stampedes, and attacks from determined predators. Along the way, he befriends a young Triceratops, a band of prancing Oviraptors, and a family of Ankylosaurs, who all help him on his journey. But when he finally finds his family, about to go to war with a rival clan of T-Rex, the loyalties he has earned, and the skills he has learned from his adventures, help save the day.