"Devious" Diesel is a devious diesel shunter, originating from the Other Railway. He is, in essence, the average pantomime villain. He is oily, malicious, devious, scheming, and full of ideas to get revenge. It appears that Diesel has a good side to him, but one would still have a deep look to find it. He does want to be a really useful engine, however, since his arrival, he has given Diesels a bad reputation. He is also very proud to be the first diesel on Sodor.
Diesel is a BR Class 08 0-6-0. Over seventy members of this class survive today in preservation. They were in fact the most successful shunting engines in the world, with 996 of them built. The Diesel Shunter, Splatter, Dodge, Arry, Bert, Paxton and Sidney are also members of the class.