Young Nate Twitchell is surprised when one of the hens on his family farm lays a giant egg. After a painstaking wait, Nate is even more surprised when it hatches and out pops a baby triceratops that he names Uncle Beazley! But when Nate decides to keep the dino and raise it on his own, he has no idea what he's getting himself into. As Uncle Beazley grows, Nate and his family realize they are not equipped to take care of a full-sized dinosaur, and so with the help of their scientist friend, Nate and Uncle Beazley set off for the Museum in Washington D.C., on the hunt for the perfect home for a modern-day dinosaur---then the real trouble begins!