Derek is a green diesel loco on the NWR. He is one of the few diesels that breaks down frequently. He currently works on Edward's Branch with the cheeky twins Bill and Ben.
Derek was built by the Clayton Equipment Company and Beyer, Peacock & Co in 1963 and worked on BR for a few months until being sent to Sodor by The Fat Controller when the work on the clay pits became too much for BoCo and the twins. On his two first days he broke down while on Gordon's hill and BoCo came with some workmen to the rescue and again when he was the banker for Bill and Ben's train. The Fat Controller soon sent Derek to the works to be mended. Later Derek returned from the works and soon became a resident of Edward's line.
Later Derek was teased by Arry and Bert for his troublesome engine then tables turned when Bert's engine broke down and Derek was sent to help get the stranded train to the docks on time. As an reward The Fat Controller decided to send Derek to the works again but this time for an overhaul and Edward arrived to take Derek who was very happy on having his engine troubles sorted out at last!
Derek is polite, jolly and highly enthusiastic about his work. He can also slightly be optimistic and always looks on the brighter side of things, Even if his engine breaks down it doesn't let him ruin his mood. He has made very close friendships with engines on the Branch especially BoCo, Edward, Bill, Ben and Bear.