|This article is about the Story Library book. You may be looking for the character or the magazine story.|
- “It's not fair! Peter Sam gets a new funnel, Sir Handel gets special wheels, passengers get ice lollies, but I'm not even polished!”
Duncan, re-titled Duncan the Stubborn Engine in 2011, is the eighteenth book in the My Thomas Story Library series.
Duncan moans about not being polished and refuses to take passengers. That night, Skarloey tells him a story about Rheneas who always put his passengers first. Duncan promises from then on to always put his passengers first.
- This book is based on the stories "Passengers and Polish" and "Gallant Old Engine" from the Railway Series book, Gallant Old Engine.
- In the fourth illustration and on the 2011 cover, Duncan is missing his number.
- Throughout the book, Duncan's cab handles disappear and reappear.
- The viaduct is not to scale.
- In the third illustration, the coach is missing a front coupling.