Thomas the Tank Engine Wikia

The twenty-first series of Thomas & Friends started airing on 18th September 2017. It is the shortest series with 18 episodes, and it was narrated by Mark Moraghan.


Originally, the twenty-first series of Thomas & Friends was written for a full twenty-six episode series, but due to the delayed productions of the nineteenth and twentieth series after The Adventure Begins was fast-tracked into Arc Productions' schedule, eight of the episodes were cancelled so that development of Big World! Big Adventures! and the twenty-second series could begin. At the time, it was unknown what the cancelled eight episodes were about, but according to Sodor Island Fansite/Forums, one of the episodes would have been about Rosie. Then, in March 2021, producer Ian McCue confirmed that the episodes Confusion Without Delay, Samson and the Fireworks (originally Oliver's Fear of Fireworks), Thomas' Animal Ark, Chucklesome Trucks, and Nia and the Unfriendly Elephant were all originally written for the twenty-first series. These episodes were pushed back to the twenty-second, twenty-third, and twenty-fourth series respectively. McCue also stated the The Christmas Coffeepot and Over the Hill were to be exclusive to the Tinsel on the Tracks DVD, hence why they were not broadcast with the rest of the twentieth series, and were instead broadcast with twenty-first series.


Screenshot Title Written by Original UK release date Episode number #
SpringtimeforDiesel.jpg Springtime for Diesel Davey Moore 18th September 2017 #01
Daisy's springs need fixing after Diesel bumps her and when the rumours spread about Daisy not being able to be mended, Diesel begins to worry.
AMostSingularEnginepromo2.png A Most Singular Engine Davey Moore 19th September 2017 #02
Diesel causes trouble between Daisy and Harvey by spreading rumours.
DowagerHatt'sBusyDay.jpg Dowager Hatt's Busy Day Lee Pressman 20th September 2017 #03
Dowager Hatt runs the railway while the Fat Controller is away, but causes confusion and delay. So, she must rely on Emily to help sort things out.
StuckinGear.jpg Stuck in Gear Davey Moore 21st September 2017 #04
A branch gets stuck in the gears of Harvey's crane, but he does not want to make a fuss about it.
RunawayEngine.jpg Runaway Engine Helen Farrall 22nd September 2017 #05
After mocking the way she was speaking up for herself, Stephen thinks that Millie ran away after hurting her feelings.
PAProblems.jpg P.A. Problems Lee Pressman 25th September 2017 #06
The Fat Controller's new public address system causes havoc at Knapford station.
HastyHannah.jpg Hasty Hannah Lee Pressman 26th September 2017 #07
A new coach temporarily replaces Henrietta while she is at the works, and causes problems for Toby.
CrankyattheEndoftheLine.jpg Cranky at the End of the Line Lee Pressman 27th September 2017 #08
Cranky thinks he will be replaced by a big, new, fancy crane.
NewCraneontheDock.jpg New Crane on the Dock Lee Pressman 28th September 2017 #09
Cranky competes against Carly the new crane when she starts taking all his work and both of them get quite the surprise at the end of the day...
UnscheduledStops.jpg Unscheduled Stops Helen Farrall 29th September 2017 #10
Thomas starts making unscheduled stops for Bertie's passengers, which in turn delays others.
Philip'sNumberpromo3.png Philip's Number Lee Pressman 2nd October 2017 #11
Philip tries to discover why he has the number 68 painted on his side after being teased about it.
TheFastestRedEngineonSodor.jpg The Fastest Red Engine on Sodor Helen Farrall 3rd October 2017 #12
After Rosie is repainted red, she and James have a race. And later, James' speedy ways cause him to crash into Tidmouth Sheds.
AShedforEdward.jpg A Shed for Edward Lee Pressman 4th October 2017 #13
Edward searches for a new shed while his berth at Tidmouth is being repaired.
TheBigFreezepromo2.png The Big Freeze Helen Farrall 1st December 2017 #14
When a big freeze hits Sodor, Diesel finally proves himself to be a hero.
EmilyintheMiddlepromo3.jpg Emily in the Middle Davey Moore 6th December 2017 #15
Emily gets stuck in the middle while helping Donald and Douglas.
TerenceBreakstheIcepromo3.png Terence Breaks the Ice Lee Pressman 11th December 2017 #16
Terence takes a shortcut across a frozen lake while collecting Christmas trees.
Daisy'sPerfectChristmaspromo2.jpg Daisy's Perfect Christmas Davey Moore 18th December 2017 #17
Daisy is disappointed when her Christmas does not go exactly as planned.
ConfusedCoachespromo.jpg Confused Coaches Helen Farrall 22nd December 2017 #18
Spencer and Gordon upset their passengers when their competitive behaviour gets out of hand.

Cut Episodes

Screenshot Title Written by Original UK release date Episode number #
MainOliverCGI.png Oliver's Fear of Fireworks Lee Pressman N/A N/A
Oliver is terrified of fireworks, and when he mistakes the sound of a warning detonator for fireworks, he is so frightened that he and Toad race off into the fog and gets lost.
ConfusionWithoutDelaypromo3.jpg Confusion Without Delay Davey Moore N/A N/A
Rebecca, a big new tender engine, comes to the Island of Sodor and works so hard not to be late that she keeps leaving stations too early.
Thomas'AnimalArkpromo.jpg Thomas' Animal Ark Lee Pressman N/A N/A
It is Christmas, and the boiler at the Animal Park breaks down, so Thomas needs to find a way to keep the animals warm.
ChucklesomeTrucksPromo.png Chucklesome Trucks Davey Moore N/A N/A
Rebecca defies expectations from Thomas, Percy and James when she works with the Troublesome Trucks and has a very amusing day.
NoImagePlaceholder.png The Unfriendly Elephant Davey Moore N/A N/A
An engine is bringing an elephant to the Sodor Animal Park, but the elephant does not like engines.


Screenshot Title Composers Original release date
RockyRescue127.png Set Friendship in Motion Kevin Roberge
Carl Taylor
Noah Berg
3rd July 2017
You can stay on the tracks
And stand still all day...
DieselandtheDucklings13.png Doing it Right (CGI version) Ed Welch 8th January 2018 (UK; DVD)
Whatever job you're doing,
Make sure you're doing it right...
Toby'sNewFriend50.png Trying (CGI version) Ed Welch 8th January 2018 (UK; DVD)
Anything that Diesels do
Steamies know that they can too...
SamsonatYourService90.png Little Engines (CGI version) Mike O'Donnell
Junior Campbell
19th March 2018 (UK; DVD)
Main Line Engines always boast how big they are,
Superior by far...


Characters Introduced



US and CAN


  • Every episode has a copyright of 2017.
  • Arc Productions had produced the first seven episodes and Terence Breaks the Ice before their bankruptcy.
  • This series contains the 500th episode of the show, P.A. Problems.
  • This series marks the third of two things:
    • The third series not to have Thomas' name titled in any of the episodes, the first being the fifteenth series and the second being the twentieth series.
    • The third series to not introduce any new engines (not counting Hannah and/or Carly). The first being the eighth series, and the second being the fifteenth series. Though Rebecca was intended to be introduced in this season.
  • This series marks the first of several things:
    • The first series to have no episodes written by Andrew Brenner during his tenure as head writer.
    • The first series to be produced by Mattel Creations.
    • The first series not to have Togo Igawa as part of the voice cast since his return in King of the Railway.
    • The first series not to have Jonathan Forbes, Olivia Colman, Jamie Campbell Bower and John Schwab as part of the voice cast since they joined the voice cast in the seventeenth series, Tale of the Brave, Sodor's Legend of the Lost Treasure and The Great Race, respectively.
    • Ian McCue's first series as creative executive and the first series to have him as part of the voice cast.
    • Micaela Winter's first series as producer for the series.
    • Sukhmani Kaur's first series as assistant production manager.
    • Zahara Andrews' first series as production coordinator.
    • Alan Kennedy's first series as director of post-production.
    • Ryan Quaglia's first series as post-production editor.
    • Gavin Ebedes' first series as supervising editor.
    • Terence, Bulgy and Farmer Finney's first appearances in full CGI.
    • Hackenbeck Tunnel, Terence's Field and Suddery Junction's first appearance in full CGI.
    • Big Mickey's first appearance with a face in the television series.
    • The first series where Caitlin appears without Connor.
    • The first series in which where Duck, Caitlin and Mike appear, but do not speak.
    • The first series since their returns in where Peter Sam and Butch appear, but do not speak.
    • The first series in which Hiro, Scruff, Connor, Marion, Samson, Hugo and Bradford do not appear since their introductions.
    • The first series in which Oliver, Whiff, Toad and Alfie do not appear since their returns.
    • The first series since the fifteenth not to introduce any new engines.
    • The first series to feature Rosie without her original lavender livery.
    • The first series since the sixteenth to have all of its episodes released in the same year.
    • The first series to have episodes fully animated by Jam Filled.
    • The first series not to be dubbed in Dutch since the twelfth series.
    • The first series not to be dubbed in German since the seventh series.
    • The first series not aired on JimJam and Minimax since the twelfth series.
    • The first series where the engines and vehicles perform non-static movements and are able to move their bodies around. This would become more prominent after Journey Beyond Sodor was finished and then next Series 21.
    • The first of three series (two if counting mini-specials) not to have an episode with that series' number per series in it, due to there only being 18 out of 26 episodes in this series that made it past the storyboards. These include, as follows (so as to avoid confusion):
      • Thomas and Gordon as the first episode of Series 1 (and also the very first ever episode overall).
      • Cows as the second episode of Series 2.
      • Time for Trouble as the third episode of Series 3.
      • You Can't Win as the fourth episode of Series 4.
      • James and the Trouble with Trees as the fifth episode of Series 5.
      • The Fogman as the sixth episode of Series 6.
      • James and the Queen of Sodor as the seventh episode of Series 7.
      • Thomas, Emily and the Snowplough as the eighth episode of Series 8 (Edward the Great, if going by production order).
      • Thomas and the Toy Shop as the ninth episode of Series 9 (Bold and Brave, if going by production order).
      • Seeing the Sights as the tenth episode of Series 10 (Topped Off Thomas, if going by production order).
      • Smoke and Mirrors as the eleventh episode of Series 11 (Thomas and the Lighthouse, if going by production order).
      • James Works it Out as the twelfth episode of Series 12.
      • Thomas and the Runaway Kite as the thirteenth episode of Series 13.
      • Thomas' Crazy Day as the fourteenth episode of Series 14 (Thomas and the Snowman Party, if going by production order).
      • Big Belle as the fifteenth episode of Series 15.
      • Whiff's Wish as the sixteenth episode of Series 16.
      • No Snow for Thomas as the seventeenth episode of Series 17 (The Switch, if going by production order).
      • Last Train for Christmas as the eighteenth episode of Series 18 (Spencer's VIP, if going by production order).
      • The first part of Diesel's Ghostly Christmas as the nineteenth episode of Series 19 (The Little Engine Who Races Ahead, if going by production order).
      • Useful Railway as the twentieth episode of Series 20 (Blown Away, if going by production order).
      • Rosie is Red as the twenty-second episode of Series 22 (Hunt the Truck, if going by production order).
  • This is the only series for a few things:
    • The only series in which Willie does not appear since his introduction in the previous series.
    • The only series since their returns in where Bill, Ben, Max and Monty appear, but do not speak.
    • The only series where Stafford, Rheneas and Oliver the Excavator appear, but do not speak since their introductions or reintroductions respectively.
    • The only series in which Farmer Finney has a speaking role, but was never referred by name.
    • The only series not to have an episode featuring Percy as the main character.
  • This series also marks the last of several things:
    • Mark Moraghan's last series as narrator for the UK and US dubs.
    • The last series to have Michael Legge as part of the voice cast and the last series where he voices Luke.
    • The last series to utilise the original storytelling format.
    • The last series to use the Engine Roll Call as the title music.
    • The last series to use the newly updated new series theme.
    • Boris Andreev's last series as art director.
    • Alan Kennedy's last series as post-production supervisor.
    • Gavin Ebedes' last series as editor.
    • The last series to have Helen Farrall as part of the writing team.
    • The final series in which the Steam Team consists of all eight of its original members.
    • The final series to have Edward, Henry and Toby as members of the Steam Team, as well as the former two as main characters.
    • The final series to have an episode where Thomas is not featured at all. From the twenty-second series onwards, he appears and narrates every episode (the latter on a permanent basis).
    • The final series where Donald, Douglas, Mavis, Stafford and Rheneas appear, although Stafford is mentioned in the twenty-fourth series episode, Kenji on the Rails Again.
    • The last series until the twenty-fourth series to not feature any fantasy sequences for several episodes.
    • The last series to use the Engine Roll Call on a regular basis.
    • The last series to air on Family Jr. in Canada. Treehouse TV in Canada took over from the twenty-second series onwards.
    • The last series not dubbed in Norwegian, Swedish, Danish and Finnish.
    • The last series to have episodes released on home media in the United States of America.
    • The last series to air its episodes within one year in the United Kingdom.
    • The last series aired by KBS 2 in South Korea.
    • The last series narrated by Kim Seung-jun in South Korea.
    • The last series to have Baek Kyung-hoon and Lee Je-in as part of the voice cast in South Korea.
    • The last series recorded and mixed by An Ho-sung in South Korea.
    • The last series translated by Kim Hye-yeon in South Korea.
    • The last series directed by Lee Won-hee in South Korea.
    • The last series to have Korean subtitles.
    • The last series aired by CBeebies in Poland.
  • This is the shortest series of the main series, with a total of only 18 episodes. Originally, a full 26-episode series was planned, but eight episodes were cut to make way for the development of Big World! Big Adventures! and the twenty-second series. In addition to this, Sodor Island Forums confirmed that the reduced total of episodes was needed to make up for the delayed productions of the nineteenth and twentieth series, due to The Adventure Begins being fast-tracked into Arc Productions' schedule.[1]
  • This is the second series for two things:
    • The second series not to be dubbed at all in Dutch, the first being twelfth series.
    • The second series to have some UK recordings released in the US, the first being the first series.
  • This series has the least dubs in other languages.
  • This series was never dubbed in European Spanish, Italian, Romanian, Dutch, German, Hungarian, Slovenian, Serbian, Croatian, Czech and Greek.
  • In the Estonian, Latvian, Lithuanian, Baltic Russian and Vietnamese dubs, UK dub can be heard in the background as a dubbing track was not used.