Thomas the Tank Engine Wikia
This article is about the engine. You may be looking for the magazine story or the Story Library book.

Duncan is a grumpy Scottish narrow gauge well tank engine who came to the Skarloey Railway as a spare engine after Peter Sam's accident with some slate trucks.


The Railway Series

Duncan was built by Andrew Barclay Sons & Co. at their Caledonia Works in Kilmarnock, Scotland to their simple and straight forward industrial design in 1928 and worked in a factory in Scotland, which Peter Sam claims is the source of his strong language and volatile temper. Duncan is powerful and can haul all but the heaviest trains, but he had been given a short wheelbase that caused him to ride roughly at speed.

In 1958, Duncan was bought secondhand by Sir Handel Lloyd Brown as a spare engine, as the workload was too much for Sir Handel and Peter Sam to manage unassisted. He came soon after Peter Sam's accident with the slate trucks and was re-gauged to 2ft 3in. Duncan was rude and arrogant at first. He often rocked and rolled along the lines, which everyone called "Rock-n-Roll." However, following accidents involving the tunnel and a worn stretch of track south of Cros-ny-Cuirn, he began to see sense and made up his feud with Rusty, whom he had detested for being a diesel. And he stopped rocking and rolling afterwards.

He was still selfish, being prone to temper tantrums and actually stalled on Rheneas Viaduct on the claims that he was overworked and not polished enough. Skarloey - fed up with his careless attitude - finally taught him sense with the story of Rheneas' single-handed running of the railway and how passengers are far more important than polish.

When some boy scouts were camping and volunteering for the Skarloey Railway, they were going to help fix a part of the line that was wet and mushy from the rain. When the scouts became thirsty, the leader stopped Duncan to help them find something for them to drink in fear that they might be dehydrated. Unfortunately, the Refreshment Lady ran out of drinks since the business was very busy for her, but Duncan suggested another tea shop near the station by the lake. They managed to pick up enough drinks and the boys cheered Duncan for helping them. He even replied by saying "It's only fair we should help you too!"

Duncan has visited the Talyllyn Railway in Wales as a tourist attraction. He was there in 2005.

Thomas & Friends

Duncan has also been very cocky, but this has often fired back at him.

Once, Rusty told Duncan a story about a ghost engine who fell off the Old Iron Bridge one night. That next morning, Peter Sam's driver had an idea and told Duncan's crew of a trick they could play on Duncan the following night for all his teasing; as Duncan was crossing the Old Iron Bridge the next night, he noticed some fireflies forming the shape of an engine which spooked him. His driver then dropped a rock into the ravine, which spooked Duncan even more and he went to his shed scared. This put Duncan in his place, thinking he had just seen a ghost.

Although Duncan is friends with Rusty, he is still rude to him and often brushes off his warnings. For example: He tried to warn Duncan about biffing slate trucks, but he doesn't listen. He ended up landing in a swamp, after being impatient and careless working on the incline railway despite. And when he warned Duncan not to cross the Old Wooden Bridge. But he ended up rescuing Duncan when he attempted to cross it anyway. And when he told him that they both had to deliver coal trucks. But Duncan ignored him and ended up being trapped in a mine. But eventually he got himself out.

Duncan likes teasing the standard gauge engines like Thomas or James when he sees either of them at the Wharf. He teased Thomas for supposedly not knowing what a Christmas tree looks like (even though Thomas did know) and once teased James saying that doing two jobs in one day is hard for a big engine like James. But soon Duncan's teasing caused problems as he heard James ran out of coal, so he came to James' rescue by bringing him some coal. He even said he was sorry for his teasing.

Duncan is well known and often teased for his temper. He has met his match before - a passenger who grumbled more than him! He also showed a lack of Christmas spirit and often grumbled about the busy work that has to be done during the festive season, even going as far as to say Ebeneezer Scrooge's quote, "Bah Humbug!" Despite his rough exterior, he heroically helped Luke up a hill around Christmas time, showing his kinder side and was rewarded with a new coat of paint.

A while later, Duncan was at Crovan's Gate when he saw Hugo race by the station. This surprised him and Sir Handel, who were both wondering if that was an engine.


Duncan is a Scottish narrow gauge engine with rough manners and a strong temper, making him the least social of the Skarloey Railway fleet. He was prone to boisterously bouncing about, which became known as "rock 'n' roll", whenever the mood took him, which once led to wedging in the north mouth of Rheneas Tunnel (probably caused by keystones knocked down by his funnel) and derailing on a stretch of line near Cros-ny-Cuirn.

While Duncan means well, he often grumbles and complains (usually about not being polished or being over-worked) and can be rude, rough, stubborn and bad-tempered. This can easily be seen in his dislike for Christmas for some reason. He claims to be a plain engine who believes in plainly speaking, an approach that can cause him to make callous or belligerent remarks. Duncan can be a competitive engine too, particularly with James. He can be impulsive, even more so than Sir Handel, and make rash decisions that usually lead to his downfall, (such as getting in arguments or short-lived feuds with Rusty). He is not always quick to apologise or realise the error of his ways. However, upon Skarloey recalling Rheneas' gallant act to get his passengers home, Duncan readily admitted he had the wrong attitude and tried hard to be a more useful, social and respectable engine in the future. When Rusty helped him after his derailment near Cros-ny-Cuirn, Duncan apologised to him and extended a wheel of friendship, proving he has gratitude.

Despite his rough ways, Duncan is often focused, confident, resourceful, kind, and has a big heart. He is always willing to lend a helping hand whenever he can and wants to be really useful.

Technical Details


Duncan is based on the Talyllyn Railway's Douglas, an Andrew Barclay "E" or "Light" Class 0-4-0WT. Between 2000 and 2015, Douglas was dressed up as Duncan for special events associated with the franchise, known as "Duncan Days". Since 2016, Edward Thomas has performed this duty, dressed as Peter Sam. Several other engines of this class are also preserved.


In the Railway Series, Duncan is painted in SR standard red with cerulean and yellow lining and with his name painted on the sides of his boiler in yellow.

In the television series, he is painted golden yellow with black lining and gold boiler bands - as of the switch to CGI, however, the lining on his cab is unpainted. He also has a brass (originally black) nameplate on the side of his boiler and a black number plate on the side of his coal bunkers. According to The Big Book of Engines, Duncan was originally painted red before coming to Sodor.


Thomas & Friends


Music Videos


Audio Files


First used Last used Sound Effect
Series 4 Active

In some scenes of the fourth series and in the fifth to twelfth series, excluding the seventh series, Duncan has his usual whistle sound at half a step higher in pitch.

First used Last used Sound Effect
Series 4 Series 12

In one scene in Passengers and Polish, Duncan is incorrectly portrayed with Duke's whistle.

First used Last used Sound Effect
Passengers and Polish Passengers and Polish

In Gallant Old Engine, Duncan is incorrectly portrayed with Peter Sam's original whistle.

First used Last used Sound Effect
Gallant Old Engine Gallant Old Engine

In Come for the Ride, Duncan is incorrectly portrayed with Skarloey's secondary whistle from the fifth to seventh series.

First Used Last used Sound Effect
Come for the Ride Come for the Ride

In The Whistle Song, Duncan is incorrectly portrayed with the same whistle sound used for the old steam whistle in the sixth series episode Scaredy Engines.

First used Last used Sound Effect
The Whistle Song The Whistle Song


  • The Rev. W. Awdry's model of Duncan is currently on display at the Narrow Gauge Museum in the Talyllyn Railway.
  • Duncan's large scale model is currently on display at the Hara Model Railway Museum in Japan and is wearing his chuckling face.
  • In some Japanese Railway Series box-artwork, Duncan is incorrectly portrayed with an 0-4-2 wheel arrangement.
  • Duncan's tendency to do "Rock-n-Roll" that resulted in incidents such as scraping tunnels with his cab and derailing were inspired from his real-life basis Douglas, who was known for being a "Rough Rider" with its short wheelbase.
  • Duncan is the only narrow gauge steam engine who has not gained a new whistle sound since his debut in the fourth series.
  • Duncan was meant to appear in The Great Little Railway Show, but he was not included as Tom Stourton had to only record one line of dialogue.
  • Duncan's happy face for his small scale model (used in the fourth and fifth series) is now owned by Twitter user Thomas Merchandise.
  • Duncan's whistle sound was sourced from the American locomotive Rio Grande No. 168.
  • In the US dub, Alec Baldwin provided a Liverpudlian accent for Duncan in the fifth series, and then provided him with a standard American accent with an obnoxious tone in the sixth series. To date, he is the only US narrator/actor in the television series to not give Duncan a Scottish accent.
  • Ted Robbins does not give him a Scottish accent in the audio narration for the story, "Pop Special".
  • Duncan's small scale model had a total of eleven facial expressions, three of which, forced-smile, angry, and startled were not used on-screen, whilst his large scale model had a total of twelve facial expressions, and they were all used on-screen.
  • Following to his introduction in the CGI series Duncan is much shorter than the other Narrow Gauge Engines. This is somewhat ironic since he was much taller in The Railway Series.
  • In the French dub, he is called Dominique.


“Who is Duncan?"
"He came as a spare engine after my accident".
"Is he useful?"
"He'll pull anything and I'm sure he means well, but he's bouncy and rude. He used to work in a factory and his language is often...strong".
"I understand",
said Skarloey gravely.
―Skarloey and Peter Sam talking about Duncan, "Home at Last", "The Little Old Engine"



* RWS only | ** T&F only