The Diseasel

The Diseasel is the twenty-first episode of the second series. It is based on the story of the same name from the Railway Series book Main Line Engines.

Plot
Bill and Ben are tank engine twins who each have four wheels, a small funnel, a tiny dome and a small cab. They work at a china clay quarry and their jobs are to take it in trucks along the main line for engines and ships. The clay is used to make many thing like pottery, paper and paint for example.

One morning, the twins arrange some trucks and leave to pick up more, but they are surprised to find they have disappeared when they return. Their drivers notice a patch of oil on the tracks and suspect that a diesel is responsible for taking the trucks. Mishearing this as "diseasel", the twins remember a notice in their shed saying "coughs and sneezles spread diseasels", and they argue over who is responsible. Their drivers intervene and make a plan to get the trucks back which involves removing the twins' nameplates and making them identical, as the diesel is unaware that they are twins.

The twins find the trucks in a yard, with a large green diesel at the front. Ben hides behind, with Bill going forward to demand the trucks back. The diesel claims the trucks are his and tries to shoo Bill away, but Bill reverses behind the trucks and Ben rides forward surprising the diesel (thinking it is the same engine). This continues for a while, causing the diesel to get dizzy. The twins then reveal themselves to him.

Edward arrives at the scene and asks what Bill and Ben are doing there. They claim that the diesel stole their trucks, but Edward scolds them for their rudeness. The twins apologise and the diesel forgives them. He introduces himself as "BoCo" and explains that he got his trucks mixed up with the twins'. Edward then sends the twins to take their lot back once they have picked up BoCo's trucks in exchange for theirs. After they leave, Edward tells BoCo that they do not mean any harm, but can be maddening at times, a statement BoCo wholeheartedly agrees with.

Characters

 * Edward
 * Bill and Ben
 * BoCo

Locations

 * Brendam Docks
 * Wellsworth
 * Wellsworth Yards
 * Sodor China Clay Company
 * Suddery Junction

Trivia

 * One barge has "Steve" written on it and a boat is labelled "Terrey." This could be a reference to crew members Stephen Asquith and Terence Permane.
 * The events of this episode were later mentioned by BoCo in the third series episode, Buzz, Buzz.
 * This episode marks with a few things:
 * The first and only time until Journey Beyond Sodor where an engine's basis is mentioned.
 * The only episode where BoCo's shocked face is used.
 * The first episode in where Bill and Ben are referred to by name, having been unnamed in their first appearance, Percy Takes the Plunge.
 * The last appearance of Suddery Junction until the twenty-first series episode, A Shed for Edward.
 * This episode is one of the few instances in which every character who appears speaks.
 * In the restored version's long distance shot of the twins at the harbour, the track that sunk into the sea can still be seen facing downward.
 * The title is a portmanteau of the words disease and diesel.
 * This is the first episode to feature sped up footage, as seen when Ben races through Wellsworth and as both twins play their trick.
 * This episode is titled "The Diseasal" on the Shining Time Station airing of Double Trouble and it is also titled "The Diesels" on the Roku Channel.
 * This episode was never released on VHS and DVD in South Korea.
 * In some foreign dubs, the portmanteau was misunderstood and the title was mistranslated as "The Diesel".

Goofs

 * One of the twins' drivers says, "We'll take away your names and numbers," but the twins were not given numbers in the television series. This is likely due to the script for the episode being taken verbatim from the original story.
 * In the restored version with the scene of Bill and Ben puffing away to fetch more China Clay, the exposed end of the set can be seen with a crew member's hands trying to catch Bill and Ben from falling off the edge of the set.
 * When Bill comes up next to BoCo, studio equipment is visible on the right.
 * When Bill and Ben annoy BoCo, the latter is missing his eyebrows.
 * When the narrator says, "Bill took his place," the track where Ben was previously bounces up.
 * When Edward arrives, his bogie is derailed.
 * When the twins apologised to BoCo, Edward disappears, indicating that the footage from where Bill was accusing BoCo of being a bully was used at that point.
 * During the scene where the twins are puffing backwards and forwards to trick BoCo, they both have Bill's whistle sound despite usually having different whistles.
 * In the shot showing Bill and Ben's cabs, a camera shadow is visible on one of them.
 * In the final shot, Edward's whistle is bent.
 * Throughout the episode, the studio is reflected in BoCo's windows.
 * When Bill and Ben puff through the level crossing and Wellsworth Station, studio equipment is seen at the top of the screen.
 * During the twins' trick, BoCo always looks at Ben whenever he comes and just stares ahead whenever Bill comes.
 * In the close-ups of BoCo looking angry in the restored version, there is greenery behind him rather than the yard.
 * In the UK dub, when the narrator says, "The twins were abashed," it shows Ben smiling, even though the word "abashed" means "embarrassed" or "ashamed."

Quotes

 * [Bill and Ben's drivers examine oil left at the scene of the crime]
 * Drivers: That's diesel.
 * Bill: It's a what'll?
 * Ben: A diseasel, I think. There's a notice about them in our shed.
 * Bill: Coughs and sneezles spread diseasels.
 * Ben: You had a cough in your smokebox yesterday. It's your fault that the Diseasel came.
 * Bill: It isn't!
 * Ben: It is!
 * Drivers: Stop arguing, you two. Let's go and rescue our trucks/freight cars.
 * Narrator: Bill and Ben were horrified!
 * Bill and Ben: But the Diseasel will magic us away like the trucks/freight cars!
 * Drivers: He won't magic us. We'll more likely magic him! [later; about the diesel] Listen, he doesn't know you're twins. So we'll take away your names and numbers and then this is what we'll do.




 * BoCo: [looks up at Bill] Do you mind?
 * Bill: Yes. I do. I want my trucks, please/cars back.
 * BoCo: These are mine. Go away!
 * Narrator: Bill pretended (not) to be frightened.
 * Bill: You're a big bully! You'll be sorry!
 * Narrator: He ran back and hid behind the trucks/cars on the other side. Ben now came forward.
 * Ben: Truck/Car stealer!
 * Narrator: He ran away too. Bill took his place. (Bill and Ben proceed to taunt BoCo several times) This went on and on 'till the diesel's eyes nearly popped out.
 * BoCo: STOP! You're making me giddy. [Bill and Ben gaze at him] Are there two of you?
 * Bill and Ben: Yes, we're twins.
 * BoCo: I might have known it.




 * Edward: Bill and Ben, why are you playing here?
 * Bill: We're not playing.
 * Ben: We're rescuing our trucks/cars. Even you don't take our trucks without asking, but this diseasel did.
 * Edward: There's no cause to be rude. This engine is a Metropolitan Vickers, diesel electric type 2.
 * Narrator: The twins were abashed/impressed.
 * Bill and Ben: We're sorry, mister(, er)...
 * BoCo: Never mind. Call me BoCo. I'm sorry I didn't understand about the trucks/cars.
 * Edward: That's all right then. Now off you go, Bill and Ben. Fetch BoCo's trucks/cars, then you can take this lot. There's no real harm in them.
 * Edward: But they're maddening at times.
 * BoCo: [chuckles] Maddening... is the word.

Merchandise

 * Buzz Books - BoCo the Diseasel
 * Magazine Stories - BoCo the Diseasel
 * Ladybird Books - Thomas Comes to Breakfast and BoCo the Diseasel
 * My Thomas Story Library - BoCo

Home Media Releases
{{Scroll box|

UK

 * The Deputation and Other Stories
 * Thomas Gets Bumped and 17 Other Stories
 * Ghost Train and other stories/Time for Trouble and other stories
 * The Biggest Ever Christmas Collection
 * The Complete Series 2
 * Edward's Exploit

DVD Boxsets

 * Classic Collection

US

 * Thomas, Percy and the Dragon and Other Stories
 * Thomas & Friends Classic Volume 2

CAN

 * Thomas, Percy and the Dragon and Other Stories

DVD Packs

 * Totally Thomas Volume 7
 * Thomas and the Treasure/Thomas, Percy and the Dragon and Other Stories Double Feature
 * On-the-Go Pack

AUS

 * The Deputation and other Stories
 * The Biggest Ever Christmas Collection
 * The Complete Series 2
 * My First Thomas with The Twin Engines

DVD Boxsets

 * Complete Series 1-10
 * Classic Collection
 * Series One and Series Two Double Pack

NZ

 * The Deputation and other Stories
 * The Biggest Ever Christmas Collection
 * Bumper Video Collection Volume 3

FRE

 * The Talkative Trains

JPN

 * Thomas the Tank Engine Volume 10
 * The Complete Works of Thomas the Tank Engine 1 Vol.4
 * The Engine Twins
 * Startled in Spite of Oneself
 * The Complete DVD Box 1

PHL

 * The Deputation

GER

 * Percy's Predicament and 4 Other Adventures
 * Thomas and His Friends Vol. 5
 * Rail Free for Steam and Diesel!

IND

 * Pop Goes the Diesel and Other Stories

ZA

 * Volume 4

UKR

 * A Train Thomas and Friends

SER

 * Thomas the Tank Engine 4

HRV

 * Better Late Than Never

GRC

 * A Lively Companionship

NOR

 * Anniversary
 * The Ghost Train

MYS

 * Thomas Comes to Breakfast and Other Thomas Adventures
 * The Deputation and Other Adventures

ITA

 * The Brave Locomotive

ROM

 * Thomas Comes to Breakfast

DVD Packs

 * Triple Pack 2

CHN

 * Thomas and Friends Season 1-4

THA

 * Thomas and Friends - Volume 7

HK
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 * Thomas and Friends Volume 5
 * Thomas and Friends Volume 6

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