Thomas' Really Useful Day is a My First Thomas-style board book.
After having his boiler stoked, Thomas is ready for a busy day's work. Thomas' first job is to take passengers to town where Thomas collects new passengers heading for the harbour. Once there, he says hello to Percy and Harold whilst his driver eats lunch before going to see the Fat Controller. Finally all the engines head back to the shed for a good night's sleep, ready for tomorrow's work.
- Percy (does not speak)
- Harold (does not speak)
- Sir Topham Hatt (does not speak)
- Edward (cameo)
- Henry (cameo)
- James (cameo)
- Toby (cameo)
- Annie and Clarabel (cameo)
- The illustration of Percy and Harold at the harbour is recycled from Meet the Engines!.
- In the second illustration, some of the red lining on Thomas' bunker is missing.