The Dinosaur is a magazine story.
A new Dinosaur Park exhibit is opening at the Sodor Museum. Huge model dinosaurs are being built and Thomas has been helping. For weeks, he has been carrying workmen and equipment to and from the museum. It is not long before the Dinosaur Park is nearly ready to open.
The Fat Controller gives Thomas the job of pulling the dinosaur special, taking everyone to the park on opening day. The museum manager later asks the Fat Controller to put up posters advertising the new park at his stations. The Fat Controller happily agrees and gives Thomas the job of taking the posters to the stations. Before he can leave, Salty arrives in the yard with a crane truck. Thomas pulls up sharply to let the dockside diesel pass. Suddenly, a coupling breaks and the crane truck hits a set of buffers hard. The crane truck topples off the rails and Harvey is called to put it back on the track. The Fat Controller tells Salty he was not to blame for the accident and Thomas says he has had a better idea on how to advertise the new Dinosaur Park. Thomas shares his idea with the Fat Controller who sends Harvey to the Works with the crane truck for a special refit.
Later on, Thomas collects the crane truck from the Works. Everyone stares in surprise as Thomas clatters past. Children point excitedly at the dinosaur Thomas appears to be pulling on a flatbed. Soon, Salty, Harvey and all the other engines see it too. They cannot believe their eyes. In no time, everyone on Sodor knows about Thomas and his dinosaur. The museum manager is delighted.
Sure enough, on opening day, a huge crowd gathers at the Dinosaur Park. Thomas carries the passengers on the dinosaur special. His carriages are filled with people eager to see Sodor's latest attraction. The museum manager is over the moon and it is all thanks to Thomas.