Thomas-saurus Rex is a book.
Thomas heard Gordon and James talking about Stepney and his old load; they thought they were too important to pull such an old load. Later Percy asked Thomas if he knew what Stepney was bringing. Thomas tries to make his voice lower so that Gordon and James won't laugh at them. Thomas likes Stepney, and he likes the story when Sir Topham Hatt and Grandfather Hatt got dirty when they rode in Stepney's freight car full of coal, because the carriage's axle broke. Stepney asks Thomas what he thinks of his load. Thomas does not want to hurt Stepney's feelings, so he said it looks old. Gordon, James, and Sir Topham Hatt then arrive. Sir Topham Hatt asks if anyone would volunteer to help Stepney up the hill, so he could deliver the load to Tidmouth. Gordon and James didn't want to help, so Thomas volunteers, and as they left Sir Topham Hatt gave Gordon a stern look. When they arrived the children were amazed at what Thomas and Stepney brought- a dinosaur skeleton.
- Sir Topham Hatt
- Grandfather Hatt
- Henry (only on the cover)
- Dowager Hatt (mentioned; not named)
- The book suggests that Sir Topham Hatt use to be called "Little Topham Hatt" in his youth.
- The cover shows Henry, but in the story, Gordon is in his place.
- The treasure chest is not on the cover.
- In the first illustration, a building was replaced by two rails and a water tower.
- Sir Topham Hatt and his Grandfather could have rode in Stepney's cab.
- Sir Topham Hatt was not dirty in the final illustration.
- A brakevan should have been added to Stepney's train.
- Stepney is said to be one of Sodor's oldest engines, but Stepney is from the Mainland.