Diesel 10 is a villainous Diesel with a roof-top, hydraulic grabber named "Pinchy".
Diesel 10 had been to Sodor a long time ago, creating problems for the steam engines. He chased down Lady - the engine who kept Sodor alive - and made her crash. In the years that followed, Lady's caretaker, Burnett Stone, took her into hiding, trying desperately, but failing to bring her back up to steam.
Diesel 10 returned many years later, intending to destroy Lady for good. He brought with him two lapdogs, Splatter and Dodge, who were present when the boss was scheming. He was first seen in the movie charging past Thomas and Gordon at Wellsworth. He also dumped sneezing powder all around Tidmouth Sheds so that the wind from Harold's blades would blow it all over the place. Diesel 10 had very little success with his plans -Mr. Conductor caused Pinchy to throw him safely onto bags of flour, and during a speech on "how to stop being stupid", he caused a coal chute to empty its contents on top of him at The Coaling Plant.
By using special coal from Sodor, Burnett Stone was able to bring Lady back to life. Diesel 10 was determined to attack her, but lost the aid of Splatter and Dodge. Burnett, Lady, and Thomas found themselves being chased by Diesel 10 over an unsafe viaduct. The center of the viaduct collapsed, and while Thomas and Lady were able to cross safely, Diesel 10 was too large and fell into a passing barge below.
How Diesel 10 got back to Sodor is a mystery. It is likely that Sir Topham Hatt decided to give him another chance.
In Diesel 10's next appearance in Calling All Engines!, he was working at the scrapyards, using Pinchy to load rusted metal into trucks. The sight of him returning caused Thomas and Percy to shudder in fright.
Thomas and Mavis went to tell steam engines and Diesels all over the island to meet at the coaling plant, a chance and hope for them to work together and get the new Sodor Airport built on time. When Thomas went over to tell Diesel 10 about the meeting, he got scared to his wheels. Not sure if Diesel 10 would want to help the steam engines anyway, due to their difficulties in the past, Thomas sped away as fast as he could.
Construction of the airport was almost complete when a tower collapsed, cracking the runway and blocking the tracks. With Harvey too far away to clear the line, Thomas took a chance and decided to ask Diesel 10. Convincing his former archenemy that helping the other engines would prove how useful he was, Thomas returned with help to clear the line.
At the end of Misty Island Rescue, unbeknownst to the steam engines, Diesel 10 was seen on a bridge overlooking the Sodor Search and Rescue Centre threatening them. He retained the comedic humour that could be seen in Thomas and the Magic Railroad; for example, when he laughs evilly, he ends up choking on his own exhaust.
He later tricked a lonely Percy into helping him take over the Sodor Steamworks. When Percy had a falling-out with Thomas, Diesel 10 used him to attempt to have the Dieselworks repaired. After convincing Thomas to go to the Dieselworks, Diesel 10 had Percy lead him and the other Diesels to the Steamworks. When they arrived, Diesel 10 betrayed Percy and takes over the Steamworks.
When Percy went to the Dieselworks to rescue Thomas, Percy saw that sparks from "Pinchy" had set the main shed ablaze. After saving Thomas and putting out the fire, Percy lead the steam engines to the Steamworks. After a brief argument between the engines, the Fat Controller arrived. Percy told him that the Diesels needed a new Dieselworks, so the Fat Controller had the steam engines and Diesels work together to rebuild it.
In the seventeenth season, Diesel 10 was stealing Christmas decorations from the Steam Team at Tidmouth Sheds with Paxton's help because he thought no one liked diesels. That afternoon, Percy caught him stealing the last of the decorations and bravely raced after the evil diesel in an attempt to get the decorations back, enlisting Edward, Thomas, James, Henry, Gordon, Toby, and Emily to help him. After taking back the decorations, Paxton told Diesel 10 that Sir Topham Hatt gave them a truckload of decorations for the Dieselworks. At the end, he decided to give the Steamies back the decorations, though most of them were crushed by Pinchy, so to compensate, he gave them the diesels' decorations because they considered Sidney to be a good enough decoration.
Diesel 10 is an evil, conniving, bullying, and psychotic monster. He absolutely despises steam engines, and would call them taunting names like "puffball" and "teapot". He is Sodor's strongest but not quite largest Diesel, his power being enforced by his slightly malfunctioning claw, Pinchy. He can use this deftly, and is even able to use it to make a sculpture. All engines, steam and diesel alike, fear and respect him.
Despite his aggressiveness, he will help on occasion since Sir Topham Hatt brought him back, but only when it suits his personal interest. He can have a caring side, but he very rarely shows it.
Diesel 10 is a BR Class 42 "Warship" with an added non-regulation hydraulic claw.
Diesel 10 is painted olive green with tan stripes.
Behind the Scenes
In Thomas and the Magic Railroad, Diesel 10 was originally played by Australian actor Keith Scott, and the character was intended only as villain supplementary to Doug Lennox's character, P. T. Boomer. Boomer was cut due to early audience reactions, and Diesel 10's role was rewritten as the primary villain. In the process, Keith Scott was replaced by Canadian improv comedian Neil Crone. Crone, with fellow improvisation comedian Kevin Frank, had been auditioning for the film to play the trucks. Crone was given the part of Diesel 10 when he was heard performing a gruff voice during auditions. In the final movie, Crone and Frank improvised much of their dialogue, including the name "Pinchy" for Diesel 10's claw.
His plan in the original script was also much different. He plotted to get rid of the steam engines by making their lives miserable, one of the sections of the plan included the "Sneezing Powder" sequence (originally the dust of quarry in the original script and Little Engines Can Do BIG Things). He also planned to destroy all the buffers on the railway so the steam engines would crash and derail, with the diesels taking over and rebuilding the buffers after. The plan to destroy the buffers were further bolstered by his discovery of the buffers that led to the entrance of Mr. Conductor's Magic Railroad, thus stopping him from continuing his plans of diesel domination. This plan was the reason why George was going to be one of his assistants. Also, instead of returning to Sodor to finally destroy Lady once and for all, he was a new engine who Sir Topham Hatt brought to help while he was away, but instead caused more havoc on the island.
- According to The Real Lives of Thomas the Tank Engine, Diesel 10's hydraulic claw, Pinchy, is an illegal modification. Among other reasons, it makes him too tall for the British loading gauge.
- In an original version of the Thomas and the Magic Railroad script, Pinchy was going to be concealed beneath Diesel 10's roof. This is kept in the book, Diesel 10 Means Trouble.
- Diesel 10's ERTL model has 8 extra wheels as it is remoulded from D199's model.
- Diesel 10 only appeared in specials and movies until the seventeenth season, where he appeared in an episode for the first time.