How the Diesel Stole Christmas is the 3-part 2013 Christmas Special. The three parts were uploaded on December 7, December 16, and December 24, 2013.
The special starts with Thomas delivering a Christmas Tree to Ffarquhar station, much to the excitement of Percy, Toby and Daisy. The other engines on the Island of Sodor are excited for Christmas, except for Diesel, who hates Christmas a lot.
Diesel's grumbling angers the other engines and scares the Fat Controller's grandchildren, much to his dismay. Later on, the Fat Controller scolds Diesel and tells him he will deliver the food for the Christmas Feast.
Diesel picks up the food from Crovans Gate as he is told, but hates the smell and doesn't listen to Skarloey and Ivo Hugh's warning about transporting food. Later on, Diesel stops at Wellsworth to rest, but leaves the trucks of food in the middle of the line despite Edward's warning.
15 minutes later, Diesel's driver tells him that his break is over and has to clear the line to allow Gordon to pass with the Express. However, Diesel refuses to move. Gordon rolls into the station but can't stop in time, so the crashes into the vans containing the food, derailing him and Edward and leaving him, Edward, and Stanley covered in squashed food, much to their anger.
Later that evening at the Diesel Works Shed, the Fat Controller scolds Diesel for his actions and tells him it was a miracle that no one died in the accident, though 31 people were injured (some seriously) and now have to spend Christmas in the hospital. He also tells Diesel that more food will have to be quickly prepared for the feast and won't be able to leave the yard for two months and calls him a "god damn fool" while Henry passes by and calls him a "Son of a Scrooge".
When Henry gets to Tidmouth Sheds, he tells the other engines about the Fat Controller punishing Diesel.
On Christmas Eve, Bertram wakes up the other Skarloey Railway engines while the other engines gossip about Diesel's incident and stupidity.
The news of Diesel's incident so spreads across the Island of Sodor.
Back at the Diesel Works Sheds, Diesel is still in a bad mood. He wants to find a way to stop Christmas from coming. He states for 56 years he's put up with it now. He eventually gets a wonderful awful idea, and tells Arry, Bert, Paxton and Sidney that they are going to steal Christmas.
Meanwhile, the engines are trying to finish up their jobs so they can get home in time for Christmas. Later that night, the engines are too excited to sleep and wish each other a Merry Christmas and a Happy New Year.
Later, the five diesels prepare to steal Christmas. Diesel is disguised as Toby, Arry and Bert are disguised as BoCo, while Sidney and Paxton remain undisguised. The five diesel engines set off. Their drivers take down the decorations and Christmas Trees around the Island while Arry and Bert derail and wreck everything. Shortly afterwards, Harold the helicopter sees Sidney, Paxton, and Diesel (mistaking him for Toby) and asks them why they are out this late on Christmas. Paxton lies and says they are delivering goods and are moving the Christmas Tree at the Fat Controller's request.
The diesels last stop is Tidmouth Sheds, where Diesel tells the other four diesels to dispose the decorations and tress at the smelters and ditch the costumes before they get there.
At the smelters yard, the diesels preparing to burn the decorations when a hallucination of Lady pops out of the molten metal and tells the diesels (who can all see her) that Diesel has corrupted himself and his friends and tells them to snap out of ruining the holiday.
Lady tells the engines that Diesel only hates Christmas because he never celebrated it on his old railway before coming to Sodor. She also tells him that she cannot decide whatever to save the decorations or not and leaves.
Diesel decides not to listen to the magical engine and decides to destroy the decorations before Paxton tells him that it's already dawn. Diesel tells the other four diesels he can't wait to see the other engines to cry "boo hoo hoo" after the find out all their decorations have been stolen.
At Tidmouth Sheds, James wakes up and screams "What happened to Christmas!?". Duck says it must've gone. The engines are all sad, but Gordon says that Christmas isn't gone and it is still here, much to the confusion of Henry, who asks how that can be since all the decorations are gone. Gordon explains Christmas can never be taken away from them and the the holiday is not about decorations, parties, trees, or presents, it's about being together and happiness. He states even if he was in a scrapyard about to be melted down, he would still have a merry Christmas. The other engines agree despite what has happened, they will still have a merry Christmas.
Meanwhile, Diesel is excited to hear everyone cry, is surprised to hear everyone singing and happy and that he and his friends didn't stop Christmas from coming, it came! Diesel is surprised that Christmas had still came, despite not coming with ribbons, tags, boxes or bags. He decides that maybe Christmas doesn't need those things and his model transforms into his 2012 model, much to his surprise and pain of the other diesels watching. Diesel has discovered the true meaning of Christmas and decides to set things right.
At Knapford Station, Thomas wishes Donald and Douglas a Merry Christmas while Donald wishes Thomas the same thing. Douglas notices Diesel returning with the decorations, the other engines are surprised and angry, thinking he stealing the decorations. Diesel explains himself to the engines and apologizes for his actions. This causes the hallucination of Diesel 10 (who has been following Diesel and telling him negative this all throughout the special) to cry out in agony and disappear.
The Fat Controller comes by, hearing Diesel's speech, tells him that he forgives him for stealing Christmas and forgives him for causing the accident two days earlier. Edward tells everyone they should get the decorations quickly put back up.
Later that evening at Tidmouth Christmas Party, Henry tells Gordon and James a dirty joke, much to their disgust. Thomas arrives and surprises Toby and Percy with his new 2012 model. Annie and Clarable have also gotten new models. Arry tries to hit on Mavis, but she tells him to get a life. The Fat Controllers wishes the viewers a Merry Christmas and tells them to look forward to a good 2014. He also thanks the viewers ans subscribes.
- Donald and Douglas
- Bill and Ben
- Arry and Bert
- Sir Handel
- Ivo Hugh
- Sir Topham Hatt
- Stephen Hatt
- Bridget Hatt
- Diesel 10 (appears as figure in Diesel's mind)
- Wretch (appears in flashback, does not speak, not named)
- Hiro (cameo)
- Stafford (cameo)
- Rheneas (cameo)
- Peter Sam (cameo)
- Rusty (cameo)
- S.C.Ruffey (singing only)
- Splatter and Dodge (original script only)
- Annie and Clarabel
- The Grinch (appears in pictures, does not speak)
- Scrap Engines (does not speak, appears in flashback)
- Bertie (appears in picture, cameo)
- Henrietta (appears in picture, cameo)
- Stephen (cameo)
- Salty (cameo)
- Toad (cameo)
- Horrid Lorry (cameo)
- Spencer (deleted scene cameo)
- Diesel: DarthWill3
- Lady and Paxton: Trevor O'Neal
- Edward and Bertram: EnterprisingEngine93
- Thomas: RightonTracks10
- Toby: James Riddle
- James: Andrew Homer
- Sidney: Connor O'Connell
- Duck: MallardFan62 (archive audio in first part)
- Oliver and BoCo: Knapford Productions
- Bill and Ben: CurtyLara2 (archive audio)
- S.C. Ruffey and Trucks Singing: Thurl Ravenscroft
- Everyone Else: Thomas1Edward2Henry3
- This special is obviously based on the book How the Grinch Stole Christmas by Dr. Seuss.
- This marks the first appearances of DarthWill3, Trevor O'Neal, RightonTracks10 ., Connor O'Connell, and KnapfordProductions as voice actors.
- This is the only time BoCo is voiced by KnapfordProductions, as he was just a temporary actor until a replacement for Tommy Davias was found, which turned out to be Andrew Homer.
- Bill and Ben's lines were recycled from Bill and Ben the Brave Brothers of Brendam because CurtyLara2 never responded to messages. The same thing applied with MallardFan8, but only in the first part. His lines were recycled from A Wretched Day for Henry and James and Gordon Goes Swimming. MallardFan8 was just having computer problems and the first part had already been uploaded by the time he had given the lines. To add to that, Rusty and Peter Sam were to have speaking roles but had to be made silent for the same reason.
- This marks the first appearance of SI3D's 2012 Thomas, Diesel, Annie, and Clarabel models, but only near the end.
- This special features music from Thomas and the Magic Railroad, Star Wars Episode II: Attack of the Clones, Doctor Who, and Inception as well as the famous song "Your a Mean One Mr. Grinch", written by Albert Hague and preformed by Thurl Ravenscroft.
- The regeneration of Diesel is obviously based on the regeneration idea from Doctor Who. In fact, the scene features a low pitch version of Vale Decem, which is heard during the 10th Doctors regeneration into the 11th.
- Gordon was originally going to have the role of Cindy-Lou Who, but the idea was dropped because of length issues.
- In the original script, Diesel 10 wasn't a figure in Diesel's mind. Diesel and his minions met him at Barrow-in-Furness as well as Splatter and Dodge to get equipment for their burglary. It was dropped because it didn't seem right to have these characters in real form, as they were only meant to be in Thomas and the Magic Railroad.
- In the original script, Diesel dressed up as Bert the Brickworks Engine from WildnorWester3D instead of Toby. This was changed for several reasons: No one would know who Bert is if they saw him (like Harold), Toby would be a more suitable disguise because of his boxy shape, and there was uncertainty that using an Asperger Syndrome Awareness character could promote controversy.
- Stafford and Stephen were supposed to have speaking roles, but Thomas1Edward2Henry3 forgot to film them.
- Stock footage from A Wretched Day for Henry and James is used as well as real pictures from Thomas and Percy's Christmas Adventure, Trouble in the Shed, Thomas' Christmas Party, It's Only Snow, Edward, Gordon, and Henry, Thomas and the Missing Christmas Tree, Escape, Not So Hasty Puddings, and the Railway Series book Stepney the Bluebell Engine.
- The drawings during the title sequence were drawn in Microsoft Paint.