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“The Steamworks is ours! It's all ours! We won't give it back now!"
"You have to give it back!"
"No, we don't and we won't! Out of my way, you
silly steamie!”
― Diesel 10 and Percy

Day of the Diesels is a 2011 feature-length Thomas & Friends special released on DVD and Blu-ray on 6th September 2011. It is the sixth Thomas & Friends film overall and follows the events of Misty Island Rescue, as seen at the end.


One summer day, Thomas is happily puffing along the tracks, until he spots smoke in the sky ahead. He finds Percy already helping to fight a fire at a farmhouse, with the Fat Controller overseeing the effort to extinguish the blaze. He starts to help fight the fire until Belle, the new fire locomotive, arrives to save the day. After the fire is put out, Belle runs out of water and Thomas and Percy shunt her to the Steamworks. Once there, Belle is congratulated by the Fat Controller for her brave work, but he says that another fire engine is needed on the Island of Sodor. Belle recommends Flynn, so it is arranged to bring him over from The Mainland.

When Thomas starts to spend all his time with Belle, Percy feels left out, and for some reason, Diesel is being nicer to him than normal. Percy is supposed to deliver Flynn's hose to the Rescue Centre, but Diesel convinces him to go to the Vicarstown Dieselworks. When Percy reaches the fork, despite Thomas earlier telling him how diesels can be devious, he takes the track to the Dieselworks. At the Dieselworks, Percy is made to feel very special by none other than Diesel 10. Percy wants to leave so that he can deliver Flynn's hose, but Diesel 10 says that Dart can take it instead. Percy learns all about the state of the Dieselworks. The diesels say that they had told the Fat Controller that the Dieselworks needed repairing, but he only listens to steam engines. Percy says that he will ask Thomas to tell the Fat Controller because he always listens to Thomas.

Meanwhile, Flynn arrives at the docks and sets off for the Steamworks. When Percy finds Thomas at the Steamworks, everyone is admiring Flynn. Percy tries to tell Thomas about the Dieselworks, but Thomas interrupts saying that the Fat Controller had asked him to show Flynn around the Island and he rolls over to the new fire engine. Percy very sadly rolls away to Tidmouth Sheds.

The next day, Percy returns to the Dieselworks and learns that they do not have a working crane. Their usual crane, Happy Hook, is in very bad shape. Percy leaves to find Thomas, but when he arrives at the Steamworks, Thomas is not there. However, Kevin is and Percy tells him all about the Dieselworks and says that if Kevin went there, Diesel 10 would call him a hero. Then Thomas arrives and tells Percy that Flynn's hose is missing. Percy again tries to tell Thomas about the Dieselworks, but Thomas puffs away to talk to Victor. Percy searches all over the island, but it soon grows dark and Percy returns to Tidmouth Sheds. There he finds that Flynn is in his berth. Very upset, he leaves and goes to the Steamworks. There he tells Kevin that he will take him to the Dieselworks and sets off with him before Kevin can say anything. Diesel 10 is delighted to have a new crane. Now that the Dieselworks has a crane, the place is soon cleared of its piled up junk.

Diesel 10 asks Percy if he had told Thomas to tell the Fat Controller about the poor condition of the Dieselworks. Percy tells him that he has not, but that he will. Diesel 10 says that Percy should bring Thomas to the Dieselworks so that they will have his full attention. Percy reluctantly agrees and spends the night at the Dieselworks.

The next day, Percy arrives at Knapford only to learn that Thomas is looking for him. Thomas then arrives and asks where Percy was. Percy tells him, but before anyone can say anything, Gordon pulls up announcing Kevin's disappearance. Percy tells everyone that he is at the Dieselworks to which Thomas asks if Victor knows. Percy admits that he does not and Thomas tells him that he must tell Victor right away.

Meanwhile, Kevin is playing with Happy Hook at the Dieselworks until Diesel 10 comes in and puts a stop to it. At the Steamworks, Percy tells everyone about the Dieselworks, but Thomas still does not listen. So Percy tells Thomas he must collect Kevin from the Dieselworks. Victor very crossly goes to tell the Fat Controller about the recent events.

Percy returns to tell Diesel 10 that Thomas will soon be there and that Victor has left the Steamworks. Diesel 10 says that Percy will lead the Diesels to the Steamworks so that they can take it over and that then the Fat Controller would listen to them. Thomas pulls in and Diesel 10 says that Den and Dart will take care of him. Den then tells Thomas to come to the back shed and he does so, reluctantly. Diesel 10 snaps his claw, accidentally causing sparks to land on some oily papers on the floor below, though neither Diesel 10, nor the other diesels notice it.

Percy leads the diesels to the Steamworks and once there, Diesel 10 betrays Percy and announces that they will not give the Steamworks back. Percy, horrified, realises that Diesel 10 has been using him this whole time to take over the Steamworks, and is not truly his friend, having finally realised the mistake he has made, Percy vows to make things right again. He returns to the Dieselworks to find Thomas and Kevin as the diesels run amuck in the Steamworks. Percy then sees that a fire had started in the main shed, and races to the Rescue Centre to get Flynn and Belle. Belle reminds them that Flynn's hose is still missing, and Percy thinks about how the diesels had tricked him and realises that the hose must still be at the Dieselworks. So the three set off to rescue Thomas, Kevin and the Dieselworks.

They arrive at the back shed and find Den and Dart holding Thomas and Kevin hostage. Percy then asks where Flynn's hose is and Dart tells him that it is in the rubbish. Belle and Flynn go to find it and deal with the fire, while Percy orders Den and Dart to let Thomas go. The two diesels initially refuse to move until Percy tells them that the Dieselworks is on fire, enabling Percy to free Thomas and Kevin.

Now that Thomas and Kevin are free, Percy and Thomas roll to the front shed and watch Flynn and Belle put out the fire. Now that the Dieselworks are safe (albeit in worse shape than before), Thomas and Percy rally their friends to reclaim the Steamworks. Before a brutal fight could break out, the steam engines promise to help the diesels if they return the Steamworks to them. Before anyone can do anything, the Fat Controller drives up along with Victor returning to see the damage to the Steamworks. Furious, the Fat Controller reprimands Diesel 10 and tells him that he will fix everything that he damaged. Before that happens, Percy, Thomas and Kevin tell the Fat Controller that the diesels are sad because their Dieselworks is old and dirty. Then the Fat Controller reveals that it was his plan all along to restore the Dieselworks anyway, but that things take time.

Soon the steam and diesel engines work well together to restore the Dieselworks. At the opening, the Fat Controller says that the new Dieselworks is special because it shows what happens when Really Useful Engines work together and that he is very proud of all of his engines. Percy rolls up beside Thomas and tells him that he feels proud and special when he is with him and Thomas says the same thing. The two best friends laugh together.


Characters Introduced




  • Ben Small as Thomas and Toby
  • Keith Wickham as Edward, Henry, Gordon, James, Percy, Salty, Den, Paxton, the Fat Controller, Dowager Hatt and the Tree Specialist
  • Matt Wilkinson as Stanley, Diesel 10, Victor, Cranky, Rocky, Kevin and Farmer McColl
  • Teresa Gallagher as Emily, Belle, Mavis, Lady Hatt and Bridget Hatt
  • Kerry Shale as Diesel, 'Arry, Bert, Sidney and Norman
  • Rupert Degas as Dart and Flynn


  • Martin Sherman as Thomas, Percy and the Tree Specialist
  • William Hope as Edward, Toby, Rocky and Farmer McColl
  • Kerry Shale as Henry, Gordon, James, Stanley, 'Arry, Bert, Sidney, Norman, Kevin and Sir Topham Hatt
  • Jules de Jongh as Emily, Mavis, Lady Hatt and Bridget Hatt
  • David Bedella as Victor
  • Michael Brandon as Diesel (uncredited)
  • Matt Wilkinson as Diesel 10
  • Keith Wickham as Salty, Paxton, Den and Dowager Hatt
  • Teresa Gallagher as Belle
  • Rupert Degas as Dart and Flynn
  • Glenn Wrage as Cranky

Bonus Features



  • "Fiery Flynn to the Rescue" game
  • Day of the Diesels karaoke song
  • Hear the Engines Coming karaoke song
  • Steamies vs. Diesels video


  • Day of the Diesels Theatrical Trailer
  • Blue Mountain Mystery Trailer


  • Nitrogen Studios began production on this special in March 2010.[1] It has a copyright of 2011.
  • Apart from laughing and cheering, 'Arry, Bert, Norman, Sidney and Paxton do not have any dialogue in this special.
  • This special takes place between the fourteenth and fifteenth series. However, it was released after the fifteenth series for unknown reasons.
  • Starting with this special, different arrangements of Percy's theme by Robert Hartshorne are occasionally featured in the show.
  • It was shown on Milkshake! during the 2011 Christmas holidays. It aired on PBS on 7th April 2012, on Nick Jr. in the UK on 3rd November 2012 and on TV 2 in Norway Boxing Day 2013, 28th December 2013, New Year's Day 2014 and Easter 2014.
  • This and Tale of the Brave are the only specials to have Percy in the leading role.
  • On streaming platforms, an instrumental piece of the song Day of the Diesels plays after the ending credits.
  • It is revealed that Thomas' driver is named Bob.
  • Teresa Gallagher joins the US voice cast.
  • This special was shown in select UK, Irish and US theatres. It was the first special shown in IMAX theatres.
  • This special marks the second time Thomas and Percy fight a fire, the first time being in the fifth series episode, Thomas, Percy and Old Slow Coach.
  • The Japanese version of this special is preceded by a two minute clip from the end of Misty Island Rescue.
  • In the UK and Irish bonus features menu, Percy's face had been edited from a serious face to a happy face.
  • Starting with this special, Peter Hartshorne joins Robert Hartshorne as composer for the specials, though Robert Hartshorne continues on solo for the episodes.
  • This special marks the first of a few things:
    • The first special narrated by Michiel de Jong in the Netherlands.
    • The first special not to have Togo Igawa as part of the voice cast since he joined the voice cast since the CGI switch.
    • Stanley's first speaking role since the his twelfth series episode, Thomas Puts the Brakes On, his first speaking role in a special since his debut in The Great Discovery and his first speaking role in a fully CGI-animated special or episode.
    • The first special not to have Thomas as the main protagonist.
    • The first special since the CGI switchover in which Spencer does not appear, although he is mentioned.
    • Charlie's first appearance in a special.
    • The first time a driver has a speaking role since the tenth series episode, It's Good to be Gordon.
    • The first appearances of Wellsworth and Norramby Fishing Village since the eleventh series episode, Percy and the Left Luggage and its first appearances in CGI.
    • The first special with Ian McCue as Producer.
    • The first special to be teased in previously, in this case being Misty Island Rescue.
    • The first special not to be released on DVD in South Korea.
    • The first special not shown at South Korean theatres since Thomas and the Magic Railroad.
    • The first-ever Blu-ray release of a preschool show in the UK and Ireland.
    • The first special not to air on Australian TV since Calling All Engines!.
  • This special also marks the last of several things:
    • The last special to have Sam Barlow involved in production.
    • The last special to have Victor be voiced by Matt Wilkinson in the UK version, as David Bedella takes over the role starting from Blue Mountain Mystery and the seventeenth series onwards.
    • The last special narrated by Blanche Ravalec in France and French speaking Canada.
    • Salty's last speaking role in a special until Tale of the Brave and thus his last appearance in a special in the Nitrogen era.
    • Gordon's last speaking role in a special until King of the Railway and thus his last speaking role in a special in the Nitrogen era.
    • 'Arry and Bert's last speaking roles in a special.
    • Diesel 10's last appearance in a special and thus his last appearance in the Nitrogen era.
  • This special marks the only of a several things:
    • The only special to have Rupert Degas as part of the voice cast.
    • The only special in which James does not have an individual speaking role.
    • The only time Kerry Shale voices Stanley in the US dub.
    • The only time Keith Wickham and Kerry Shale voice Paxton and Sidney respectively.
    • Sidney's only appearance until the seventeenth series episode, The Missing Christmas Decorations and thus his only appearance in the Nitrogen era.
    • The only time Belle blows her whistle in the Nitrogen era.
    • The only special to receive a UK and Irish Blu-ray release.
  • The following scenes from the Day of the Diesels trailer were not seen in the special:
    • Belle squirting water from her water cannons whilst on the move. This scene was from the fifteenth series episode, Big Belle.
    • Flynn going along the Fenland Track.
    • Flynn meeting children at the School.
    • Flynn fighting a fire at the Woods whilst the fireman shoos away some squirrels. This and the above scenes were from the fifteenth series episode, Fiery Flynn.
    • On his way to rescue the Dieselworks with Belle and Percy, Flynn said "Here I come, Thomas! Fiery Flynn to the rescue!"
    • The Fat Controller's line, "The diesels have caused confusion and delay!"
    • Percy saying "Thomas is in danger!"
  • From this special onwards, Salty has Derek's horn sound.
  • At one point in this special, the brake sound effect from the model series is reused.
  • This special won top spot in Tesco's DVD family chart.
  • According to Sam Barlow, the film originally had some scenes which were deemed too scary for children and Diesel 10 would have been voiced by Rupert Degas.
  • This special was released the year the final book of the Railway Series was published.
  • According to Ian McCue, Splatter, Dodge and Dennis were originally intended to return in this special. However, they were later cut in favour of Paxton, Sidney and Norman.[2] As these three share the same respective basis as the former three engines, therefore technically making them all related. Had these changes been retained, this could have marked Dennis, Splatter and Dodge's first appearances in full CGI, and this would have also marked the return of Splatter and Dodge since Thomas and the Magic Railroad. This would have also been their first appearances in the main series outside of said special and Dennis' since The Great Discovery, as well as his first speaking role since the ninth series episode, Thomas' Day Off and it would have been their only appearances in the Nitrogen era.
  • This special reuses some elements from the twelfth series episode, Best Friends as it involves Thomas and Percy having a fallout.
  • This is the third special not dubbed in Hebrew and the fourth not dubbed in Italian.
  • This and Thomas and the Magic Railroad are the only specials not to have a trailer in South Korea.
  • When the diesels take over the Steamworks, a rendition of the music piece 'In the Hall of the Mountain King' can be heard.
  • This special was planned to be shown at South Korean theaters in 2012, hinted by the VOD's release labeling "Let's see it first before we see it in theaters." However, this plan did not go forward.
  • There is a rare chance of getting a ticket from the Complete Series 12 DVD.


  • In the first shot of the fire, there are suddenly three tracks instead of two like there had been just prior.
  • In the opening scene of Thomas puffing down the tracks, the first scene is cloudless, but just after puffing round the bend noticing the black smoke and just as he pulls up next to Percy to help fight the fire, clouds suddenly appear.
  • It is said that Thomas and Percy buffer up to Belle, but all three engines are on different tracks.
  • When Percy enters the Steamworks while Thomas and Belle are there, Percy's wheels are rotating slower than he is moving.
  • After the narrator says, "And into the shadow of Diesel 10," for a split second as the scene fades in, the scene is frozen.
  • When Percy puffs away from the Steamworks with Kevin, the flatbed is not rendered properly.
  • When Percy arranges for Thomas to fetch Kevin from the Dieselworks, his body has shifted downwards.
  • On the front cover of the DVD, Salty's bufferbeam is restored instead of weathered. The prototype, however, shows it as weathered.
  • In the German dub, the title is "Dampfloks gegen Dieselloks," but the narrator says "Dieselloks gegen Dampfloks."
  • Thomas' driver looks different during the fire scene.
  • Michael Brandon is not credited in the US dub for voicing Diesel.
  • When the steam engines tell Gordon and James about the diesels' takeover, Edward's wheels suddenly stop moving.
  • In the bird eye's view of Wellsworth, a flatbed can be seen standing on the road behind one of the platforms.
  • When the steam engines enter the Steamworks, Percy has Thomas' whistle sound.
  • In South Korea, this special is stated to be the fourth Thomas movie.
  • In the scene were Diesel 10 is on the turntable in the Steamworks, the wheels of Diesel, 'Arry and Bert are moving backwards.
  • 'Arry and Bert have Salty's horn

In Other Languages

View content
Language Title
Chinese Mandarin 柴油火车的秘密行动
Czech Diesel má slavný den
Danish Dieselenes dag
Dutch Stomers Tegen Diesels
Finnish Dieselien päivä
French Bazar chez les locomotives
German Dampfloks gegen Dieselloks
Greek Περιπέτεια με τις Ντιζελομηχανές!
Hungarian A dízelek napja
Indonesian Hari Mesin Disel (VCD)
Disel dan Kereta Api Uap (RTV)
Japanese ディーゼル10の逆襲
Korean 디젤의 반란 (2012)
디젤 기관차들의 반란 (2018)
Latin American Spanish Día de los Diesel
Norwegian Dieselenes dag
Polish Dzień Diesli
Portuguese Dia dos Trens a Diesel
Romanian Ziua Locomotivelor Diesel
Russian День Дизелей
Serbian Dan dizela
Slovenian Dan dizlov
Swedish Dislarnes dag
Turkish Dizellerin Günü

DVD Boxsets





Wooden Railway

  • Percy at the Dieselworks set (discontinued)
  • Thomas and Belle to the Rescue set (discontinued)
  • Flynn and Water Tower Figure 8 Set (discontinued)
  • Mavis and Fuel Tanker (discontinued)
  • Diesel Fuel Depot (discontinued)
  • Steamies vs. Diesels (discontinued)
  • Flynn (discontinued)
  • Belle (discontinued)
  • Dart (discontinued)
  • Den (discontinued)
  • Sidney (discontinued)
  • Norman (discontinued)
  • Paxton (discontinued)


  • Dart (discontinued)


  • Brave Belle (discontinued)
  • Oil and Trouble Dart (discontinued)
  • Fiery Flynn (discontinued; redesigned and re-released in 2014)
  • Den at the Dieselworks (discontinued)
  • Diesel 10 Takes Charge (discontinued)
  • Dieselworks Delivery (discontinued)
  • Cranky and Flynn to the Rescue set (discontinued)


  • Flynn
  • Belle
  • Fire Engine Flynn and Diesel 10 Rescue
  • Fire Engine Flynn and Thomas set


  • Thomas, Percy and Diesel 10 set


  • Den (discontinued)
  • Dart (discontinued)
  • Belle (discontinued)
  • Flynn (normal and talking; discontinued)
  • Sidney (discontinued)
  • Paxton (discontinued)
  • Norman (discontinued)
  • Percy and Kevin to the Rescue (discontinued)
  • Thomas to the Rescue (discontinued)
  • Talking Percy at the Dieselworks (discontinued)
  • Talking Diesel's Fuel and Freight Delivery set (discontinued)
  • The Dieselworks (discontinued)

Mega Bloks

  • Den (discontinued)
  • Dart (discontinued)
  • Day at the Dieselworks set (discontinued)
  • Flynn's Rescue set (discontinued)
  • Diesel Small Bucket set (discontinued)

Capsule Plarail

  • Flynn
  • Belle
  • Den
  • Dart
  • Dieselworks

Collectible Railway

  • Flynn
  • Belle
  • Diesel's Load and Go

Pocket Fantasy

  • Cinema Set (includes playmat with Thomas, Percy, Oliver, Diesel 10, Hiro, Belle, Flynn, Den, Harold and Sir Topham Hatt) (discontinued)



* Rental only