Percy suffers from this on a few occasions, mainly in episodes such as "Put Upon Percy" and "Percy's Chocolate Crunch". The Reverend Awdry made cameos in the Railway Series and in Sodor's Legend of the Lost Treasure, where he was known as, in the Railway Series at least, as the Thin Clergyman.

Thomas, Percy and the Coal" may also count. Apart from the first few scenes, the episodes takes place entirely at the Tidmouth complex. The episode is believed to have replaced The Missing Coach, so this was probably done to save time and money. A Christmas Quire. Sarn & Chang Mai, Thailand: Frangipani P., 2009. [Collection of poems related to Christmas, with illustrations by Elsi Eldridge, published by Gwydion Thomas, in a private limited edition.] Adaptation Title Change: The series goes by Thomas the Tank Engine & Friends (later shortened to Thomas & Friends) as opposed to the title of the original novels that it’s based on, The Railway Series.Westover, Daniel. “‘An Echo of an Echo’: R.S. Thomas and Geoffrey Hill”, International Journal of Welsh Studies 1 (2013): 1-18.

Famous locomotives City of Truro and Flying Scotsman in "Gordon and the Famous Visitor" and "Tender Engines" respectively. Starting in Season 23, the engines became much more detailed, with such things as rivets, handrails, and various other realistic little things that had been missing from the Nitrogen and Arc models.Character Name and the Noun Phrase: Many episode titles follow this format, especially in the form of "Thomas and the....." R.S. Thomas: Poezija za vecerjo. Zalozba: Mladinska knjiga, 2013. ISBN 978-961-01-2773-4. [Slovenian translations.]

McGill, William J. “Cross-Pollination: George Herbert, R.S. Thomas and ‘The Flower’”. Topic: A Journal of the Liberal Arts 50 (2000): 59-69. Thomas Comes to Breakfast. When Thomas skids off the rails and crashes into a house, just as the family within is sitting down to breakfast, the stationmaster's wife is more upset about her ruined pancakes that the freakin' locomotive that just drove into her living room.Das Himmelreimende Kind / The Sky-Rhyming Child. Trans. Kevin Perryman. Denklingen: Babel, 2013. English-German bilingual edition. Thomas Lanier Williams, American playwright known as Tennessee Williams, considered one of the great dramatists of the 20th century

On a positive note, "Henry's Forest" handled the Green Aesop pretty well. Helps that it was an early episode, and that the last scenes are very pretty. R.S. Thomas in conversation with Molly Price-Owen”, David Jones Journal Summer/Autumn 2001 (R.S. Thomas Special Issue): 93-102. (See under 2.i Books) Pikoulis, John. “R.S. Thomas: composer of the first radio-active verses”. New Welsh Review 40 (1998): 13-18. (Review essay on R.S. Thomas, Autobiographies.)

Cannot Keep a Secret: Thomas can't resist telling a downbeat Stephen about his special job in King Of The Railway, pivoting the chain of events. Subverted in Blue Mountain Mystery, the narrow gauge engines think Thomas blabbed about Luke in trying to clear his name, but he did so via shrewd investigation. Cofio RS: Cleniach yn Gymraeg? Caernarfon: Gwasg y Bwythyn, 2013. 144p. ISBN 978-1-907424-44-1. [‘Remembering RS: Kinder in Welsh?’ Recollections by those who knew him, including friends and neighbours. Finely illustrated, including previously unpublished pictures of RST and drawings by Elsi Eldridge.] Thomas from the Bible, one of the 12 apostles of Jesus. He is best known for the post-Resurrection moment where he asks for proof that Jesus has really returned from the dead. This scene is the origin of the phrase “Doubting Thomas” Savill, Sheila. “The Value of Official Records to Studies of R.S. Thomas’s Life and Writings”, Almanac: A Yearbook of Welsh Writing in English 15 (2010-11): 84-111. One episode of "Thomas' Comedy Showtime" on the official YouTube channel takes two potshots at the Nitrogen era. First calling Mr. Bubbles a "textbook clown" while commentating on Slippy Sodor, and saying there's nothing funny about a giant balloon while commentating on " Up Up and Away".