Percy is a small green engine.
- Troublesome Engines - Trouble in the Sheds and Percy Runs Away
- Henry the Green Engine - Gordon's Whistle and Percy and the Trousers
- Toby the Tram Engine - Dirty Objects and Mrs. Kyndley's Christmas
- Gordon the Big Engine - Off the Rails and Paint Pots and Queens
- Edward the Blue Engine - Cows (does not speak), Saved from Scrap (cameo) and Old Iron
- Four Little Engines - Sir Handel (cameo) and Old Faithful (cameo)
- Percy the Small Engine - Percy and the Signal, Duck Takes Charge, Percy and Harold and Percy's Promise