Travelling Thomas is a magazine story.
The Fat Controller owns an old-fashioned wooden caravan that is his prize and joy. When he first purchased it, he spent all his spare time mending and painting it. One day, the Fat Controller sets off for a week's holiday with his wife during which time they plan to tour the Island of Sodor in their colourful travelling home. As he watches the caravan disappear into the distance, Thomas wishes he could have a holiday, too.
Later, as Thomas puffs along his branchline, the driver spots a red flag ahead and quickly applies the brakes. It's the Fat Controller. His caravan has slipped on some mud and come off the road. Luckily, the controller and his wife are unhurt, but their broken caravan is now across the railway line. Thomas knows how to help and races back to the station to fetch Harvey. As the crane engine lifts the caravan up, he can see it's not badly damaged.
Meanwhile, Thomas fetches a long flatbed truck from the goods yard. Thomas slowly backs up to caravan and Harvey lowers it onto the truck where it is safely secured. Thomas offers to take the caravan to the works, but the Fat Controller tells Thomas to take it to the paint shop instead. Thomas is puzzled; the caravan needs mending not painting. Then, Lady Hatt arrives with some flowers for Thomas who thinks the whole scenario is very odd.
The Fat Controller declares that the holiday will go ahead. Only, this time, the caravan is pulled by Thomas while the horse is sent back to the stable for a much needed rest. Adding to the holiday mood, Thomas' flatbed is painted in bright colours to match the caravan. Then, Thomas is decorated with the flowers that Lady Hatt had given him.
Thomas feels proud and happy to be puffing slowly around the island with the splendid caravan behind him. His wish has come true, he's having a holiday after all.