|This article is about the Buzz Book. You may be looking for the episode, the DVD, or the magazine story.|
Thomas is boasting about being blue as he thinks it's the only colour for a really useful engine. Later, he runs into trouble when he gets covered in coal. Percy laughs, but Thomas has the last laugh when Percy rolls off the tracks and ends up wheel-deep in coal. The engines soon make up their quarrel and become best of friends.