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The Diseasel

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This article is about the episode. You may be looking for the Buzz Book or the magazine story.
"It's a what'll?"
"A Diseasel, I think. There's a notice about them in our shed."
"Coughs and sneezles spread Diseasels!"
"You had a cough in your smokebox yesterday! It's your fault the Diseasel came!"
"It isn't!"
"It is!
— Bill and Ben

The Diseasel is the twenty-first episode of the second season. In the US it first aired on the Shining Time Station episode, Double Trouble in 1991.


Bill and Ben are tank engine twins who work at a china clay quarry. Their jobs are to take the china clay in trucks along the main line for engines and ships.

One day, Bill and Ben arrange some trucks and leave to pick up more, but return to find them gone. Their drivers find a patch of oil on the ground and realise a diesel is responsible for taking the trucks. Mishearing this as "diseasel", the twins argue who is responsible stating that "coughs and sneezles spread diseasels". The drivers stop the twins from arguing and make a plan to get the trucks back which involves removing the twins identifying plates and making them identical.

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 when Bill disappears Ben rides forward surprising the diesel (thinking it's 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 explain that the "dieseasel" 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 Bill and Ben's. Edward then sends the twins to pick up BoCo's trucks.

After the two leave, Edward tells BoCo that Bill and Ben do not mean any harm but can be maddening at times. BoCo laughs and replies that "maddening is the word".




  • This episode is based on the story of the same name from The Railway Series book, Main Line Engines.
  • As Bill and Ben puff into the shed near BoCo's train, to the left of the shed, there is a soup can in the foreground.
  • 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.
  • This is the second episode where no characters cameo, the first being Down the Mine.


  • One of Bill and Ben's 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 nearly identical word-for-word to the original story.
  • In the restored version, when Bill and Ben leave Brendam Docks, the twins do not disappear. They just stop right at the top of the screen. The end of the set can be seen in a still from the episode: also, two hands can be seen pulling them backwards with string.
  • Bill and Ben are said to puff into the shed behind BoCo when they actually are in the shed next to him.
  • The narrator says Ben (on BoCo's right) went forward, but he goes to the left in the next shot.
  • When Ben comes up next to BoCo, BoCo looks to his right, but when Bill comes up BoCo does not look to his left.
  • 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 apologise to BoCo, Edward disappears, indicating that the footage from where Bill was accusing BoCo of being a bully was used at that point.
  • In some restored versions, when the twins puff away for more trucks you can see 2 hands drop to catch the twins models.
  • During the scene where the twins are puffing backwards and forwards to trick BoCo, they both have the same whistle sound despite usually having different whistles.


In Other Languages

Language Name Meaning
Croatian Dizel Dolesti Diesel Disease
Japanese ふたごのビルとベン Bill and Ben the Twins
Spanish Problemas De Mellizos Twin Problems
Polish Chorobowóz Disease-Diesel
Norwegian Disyselen The Diseasel
German Dieselitis Dieselitis
Italian Solo Un Equivoco Only A Misunderstanding
Hungarian A dízelmozdony The Diesel Locomotive
Finnish Tautinen The Diseasel
Chinese 生病了 Sick
Korean 빌 과 벤 Bill and Ben
Slovenian Dizelska lokomotiva Diesel Locomotive
Russian Простудизель Prostudizel
Ukrainian Дизентиризиль Dyzentyryzel
Czech Diesel Diesel
Romanian Dieselul The Diesel
Slovak Diesel Diesel
Swedish Disyselen Diseasel
Dutch De Viesel The Diesel
Danish Bill og Ben og vogntyven Bill, Ben and the Car Thief
Thai หัวรถจักรแฝดใหม่คู่ที่สอง Engine Detached Two New Pairs
Brazilian Portuguese O Diesel The Diesel

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