THOMAS the Tank Engine was a popular kids’ TV show that many adults remember fondly from their childhood.

But recently a clip has resurfaced from the “innocent” programme showing a dark side that some have likened to a “horror story” thanks to its chilling storyline.

7 Fans have been shocked at watching a scene from Thomas the Tank Engine when Henry gets 'sentenced to death' for not going to work Credit: Thomas the Tank Engine & Friends, Gullane Entertainment

7 In the episode Henry refuses to emerge from the tunnel in the rain in case it ruins his nice green and red paintwork Credit: Thomas the Tank Engine & Friends, Gullane Entertainment

7 The Fat Controller insists that Henry be imprisoned inside the tunnel forever Credit: Thomas the Tank Engine & Friends, Gullane Entertainment

Twitter user Tristan Cooper spotted the dark scene and wrote on Twitter: "There's a Thomas the Tank episode where a stubborn train is punished by being entombed alive forever and it's worse than any horror movie".

The clip is from episode three of Thomas & Friends which tells the tragic story of “stubborn” train Henry who was “sentenced to death” for not going to work.

In the episode Henry refuses to emerge from the tunnel in the rain in case it ruins his nice green and red paintwork.

After using ropes and much persuasion, the Fat Controller eventually gives up trying to get him to come out and instead insists that Henry be imprisoned inside the tunnel forever.

In the clip he can be seen speaking to poor Henry commanding: “We shall take away your rails and leave you here for always and always and always.

Henry can be seen looking visibly distressed as a brick wall is built to trap him in the dark tunnel.

There's a Thomas the Tank episode where a stubborn train is punished by being entombed alive forever and it's worse than any horror movie pic.twitter.com/Bn1Y0PTItL — Tristan Cooper (@TristanACooper) September 28, 2017

7 Henry looks visibly distressed as a brick wall is built to trap him in the dark tunnel Credit: Thomas the Tank Engine & Friends, Gullane Entertainment

7 The other trains can be seen whizzing by, which one saying Henry deserved his fate Credit: Thomas the Tank Engine & Friends, Gullane Entertainment

And to make matters worse, he received little sympathy from the other trains happily whizzing by with one shouting out “serves you right”.

The narration tells how poor Henry had no steam to answer and his fire had gone out.

The last line of the commentary is particularly chilling, with the storyteller saying: “I think he deserved his punishment, don’t you?”

Viewers were quick to share their horror at fully comprehending the clip, years after watching it as a kid.

One commenter wrote: “What moral lesson are kids supposed to learn from this? Do as you’re told or you will be entombed forever in the darkness to die?”

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In the New Yorker, writer Jia Tolentino went as far to criticise Thomas the Tank Engine creator Reverend Wilbert Awdry, who first published The Railway Series in 1945.

She argued: “It is clear from his work that Awdry disliked change, venerated order, and craved the administration of punishment. Henry wasn’t the only train to receive a death sentence.”

Another train to receive a less-than-pleasant fate is that of a show-off engine called Smudger, who is told by a manager he will “make him useful at last.”

Smudger is then turned into a generator and never moves again, meanwhile in a different scene a “spiteful” brake van is crushed.

7 The narration tells how poor Henry had no steam to answer and his fire had gone out Credit: Thomas the Tank Engine & Friends, Gullane Entertainment

Jia observed: “In another episode, a double-decker bus named Bulgy comes to the station and talks about revolution — ‘Free the roads from railway tyranny!’ he cries. He is quickly labelled a ‘scarlet deceiver’, trapped under a bridge, and turned into a henhouse.”

Her article also suggests that the railways series implements a caste system via an “authoritarian rule through disinformation.”

Jia adds: “There is one diesel engine who struggles to prove that he’s as useful as the steam trains.

“Less useful than Diesel are the female passenger coaches named Annie and Clarabel, who are awarded to Thomas as prizes after he helps with a train breakdown.”

7 The last line of the commentary is particularly chilling, with the storyteller saying: 'I think he deserved his punishment, don’t you?' Credit: Thomas the Tank Engine & Friends, Gullane Entertainment

In 1979, British producer Britt Allcroft came across Reverend Wilbert’s books that he created for his son Christopher.

Britt arranged a deal to bring the tales to life as the TV series Thomas the Tank Engine and Friends (later simplified to Thomas & Friends), which became an award-winning hit show.

It has aired for around 20 seasons in one form or other, and in 2009 production went CGI.

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