Diesel 10, also known as Diesel, is an evil diesel engine with a hydraulic claw, which he has nicknamed "Pinchy". He is one of the steam engines' oldest enemies, and has proven himself to be a rather dangerous foe.
Thomas and the Magic Railroad
Diesel 10 once came to visit the Island of Sodor a long time ago, but caused problems for the steam engines while he was there. During his visit, Diesel 10 discovered Lady, the engine responsible for keeping Sodor alive, and he chased her down. Lady ended up going too fast and ran out of coal, and Diesel 10 crashed her. Following the accident, Lady's caretaker, Burnett Stone, took her back to his workshop in Muffle Mountain to protect her from Diesel 10, and for many years tried desperately to bring her back up to steam, but did not have the coal needed to make her run.
Several years later, Diesel 10 returned to the North Western Railway when the Fat Controller was on holiday, and proceeded to make life on the island harder for the engines. He was determined to destroy Lady once and for all, and brought along his two bumbling sidekicks, Splatter and Dodge, to help him carry out his plans. He dumped sneezing powder around Tidmouth Sheds, and later destroyed the scaffolding beside the roundhouse, taunting Mr. Conductor for losing his gold dust.
Mr. Conductor knew he had to search for more gold dust and tried to look for the windmill, but got lost. As he was walking along, Diesel 10 found him and picked him up with his claw, holding him over a viaduct and intended to drop him if he did not tell him where the magic buffers were. Mr. Conductor managed to escape by using a pair of wire cutters to cut the hydraulics to Diesel 10's claw, causing him to throw him in the air and drop him at the windmill. Diesel 10 defended himself when Splatter and Dodge asked him why he had done that, claiming he did it "on purpose" and proceeding to hit the coal hopper with his claw, but was buried under a pile of coal.
Diesel 10 was later cruising along the Main Line, when Junior landed on his cab roof after he had been launched in the air by the windmill's sails. Diesel 10 raced across the island with Junior on his cab and stopped at the scrapyards, where he tried to push him and James into the melting pot. Fortunately, Junior and James managed to escape when the former used the last of his gold dust to teleport them out of the scrapyards.
When Lady came back to life and returned to Sodor, Diesel 10 found her and began to chase her, Burnett and Thomas. He chased the three across the island, until they began to approach the collapsing viaduct. Lady, Burnett and Thomas managed to cross the bridge safely, but Diesel 10 was too heavy for the weakened rails and fell off the viaduct. Diesel 10 held onto a sleeper and called out to Lady and Thomas, but the sleeper broke off the rails and he fell in a barge full of sludge. Diesel 10 was sent away in disgrace afterwards. (Film; Thomas and the Magic Railroad)
Diesel 10 later returned to Sodor under unknown circumstances, and began working at the scrapyards, where he was given the task of loading scrap metal into trucks. He was first seen by Thomas and Percy when the two came to the scrapyards, his very presence causing the two to shudder in fright.
When the steam and diesel engines were holding a meeting at the Coaling Plant to end their feud and work on the Sodor Airport, Thomas was sent to the scrapyards to inform Diesel 10 about the meeting. However, when he arrived at the scrapyard, Thomas became too frightened to speak to him and believed that Diesel 10 would not want to help anyway due to their difficulties in the past, so he sped away before Diesel 10 could see him.
The steam and diesel engines managed to work on the airport without Diesel 10, and soon construction on the airport was nearly complete, until a water tower collapsed and cracked the runway. As Harvey was on the other side of the island, Thomas went to ask Diesel 10 to help them clear the wreckage. After some hesitation, Diesel 10 agreed to help out, and he managed to clear the line in time. (TVS; Calling All Engines!)
After Thomas was found prior to the reopening of Great Waterton, Diesel 10 was among the diesels present at the quarry when they heard the news. (TVS; The Great Discovery) Later, when the Sodor Search and Rescue Centre was opened, Diesel 10 stood on a cliff overlooking the rescue centre, and threatened to come back. (TVS; Misty Island Rescue)
When Percy was becoming distant from Thomas, Diesel 10 saw this as an opportunity to manipulate Percy into helping him restore the Vicarstown Dieselworks. With the help of Diesel, Percy arrived at the Dieselworks, where he befriended Diesel 10. When the time came, Diesel 10 ordered Thomas to come to the Dieselworks, where he was held hostage by Den and Dart while he, Percy and the other diesels went to the Steamworks. When they arrived at the Steamworks, Diesel 10 betrayed Percy and took over the Steamworks with the other diesel engines.
Percy raced back to the Dieselworks to rescue Thomas, when he discovered that sparks from Diesel 10's claw had set the main building of the Dieselworks ablaze. After he rescued Thomas and the fire was put out, Percy led the Steam Team and Kevin to the Steamworks, where they confronted Diesel 10 and argued with him until the Fat Controller arrived. After Percy explained that the diesels needed a new workshop, the Fat Controller agreed to have the Dieselworks restored. Diesel 10 helped with the reconstruction of the Dieselworks and became the head of the workshops, with Den and Dart taking over in his absence. (TVS; Day of the Diesels)
When it was Christmastime, Diesel 10 became jealous when the Steam Team had more decorations at Tidmouth Sheds than the diesels did at the Dieselworks, and decided to steal the decorations from their sheds, enlisting a reluctant Paxton to help him out. When he was stealing a strand of garland from the sheds, Diesel 10 was caught by Percy, who chased him all the way back to the Dieselworks with the rest of the Steam Team. Diesel 10 told the engines that he was jealous of them for having more decorations, until he discovered that the Fat Controller had more decorations for the diesels and had arranged for Paxton to bring them to the Dieselworks. Feeling guilty for what he had done, Diesel 10 returned the decorations to the Steam Team as well as giving them the diesels' own decorations, as he and the other diesels considered Sidney to be a good enough decoration. (TVS; The Missing Christmas Decorations)
Diesel 10 is based on the British Rail Class 42 "Warship" diesel-hydraulic class, which were introduced in 1958 and built at the BR Swindon Works. Two "Warships" have been preserved; D821 "Chris Broadhurst" on the Severn Valley Railway, and D832 "Onslaught" on the East Lancashire Railway. Diesel 10 is also fitted with a large hydraulic claw, which can spin around 360° and can be raised and lowered. The bucket of his claw can also twist into different positions, and can be used for a number of things, such as carving sculptures into the side of cliffs, pick up scrap metal and so on.
Diesel 10 is painted olive green with beige stripes on his sides. His bufferbeam is painted red, and his wheels, air vents and buffers are black. His claw is painted dark brown, which has become progressively darker in later appearances.