The show is set in a whimsically realistic, prehistoric world of jungles, swamps, active volcanoes and oceans, all teeming with dinosaur and animal life, and connected by a shining train line known as the Dinosaur Train. This steam-engine train is customized for dinosaurs of all kinds: windows accommodate the long-necked sauropods, there’s plenty of headroom in the Observation Car, and the Aquacar is an aquarium for sea-going passengers. The train itself is run by Troodons (who get to run it because they’re the smartest dinosaurs, as they often explain, and have nimble toe claws to punch the tickets). The Dinosaur Train circles the whole world—it even crosses the oceans and inland seas, with stops to visit undersea prehistoric animals. It also has the ability to visit the entire Mesozoic Era, the “Age of Dinosaurs”, passing through magical Time Tunnels to meet the dinosaurs in the Triassic, Jurassic, and Cretaceous time periods.
The world of Dinosaur Train is seen through the eyes of Buddy, the preschool-age Tyrannosaurus rex. In the show’s main title song, we learn that Buddy was adopted by Mr. and Mrs. Pteranodon and brought to their nest to hatch at the same time as his siblings Tiny, Shiny, and Don. By traveling in the Dinosaur Train around the Mesozoic, assisted with all dinosaur facts by the train’s Troodon Conductor, Buddy quickly learns that he is a T. rex. As an adopted kid in a mixed-species family, Buddy is especially curious about the differences between species and vows to learn about all the dinosaurs he can by riding the Dinosaur Train.