|This article is about the character. You may be looking for the story.|
After Rex's steampipe began leaking one day and Frank had to take his train, the Small Controller began thinking they needed another engine and so he arranged for Jock to be built. When Jock first came out for testing he was still unnamed. Jock's paint colour reminded Douglas of his days on the Highland Railway and suggested the name "Jock" for the new engine. The Small Controller and Jock liked the name so it stuck. Later, he pulled a doubleheader with Mike.
Jock was very cocky when he was first built, as a result of being rather strong, but soon learned the value of teamwork when Mike's injector failed and he had to pull Mike and his train single-handedly.
Jock is painted in the Highland Railway chartreuse yellow livery with red lining. He has a brass dome, brass builder's plates on the sides of his cab, red nameplates with gold writing mounted on each side of his boiler and "ARLESDALE" written on the sides of his tender in yellow.
Jock also appeared in the book, James and The Fat Controller.
- Jock was the last ERTL toy to be made in the range. His tender is also based on the one illustration where his tender erroneously has a dip at the back.
- Jock was mentioned in The Island of Sodor: Its People, History and Railways, but his first appearance was not until Jock the New Engine.
- ERTL (discontinued)