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“My beautiful concrete!"
"My beautiful blue paint!”
―Patrick and Thomas complaining about the aftermath of the accident

On Site with Thomas, originally known as Who's the Boss, is the third episode of Jack and the Sodor Construction Company.


During the construction of the community centre, Patrick boasts that he is the most important because he is a concrete mixer. This makes Jack and Alfie curious about who really is the most important. Jack asks Byron, who claims that he is, as he levels the site. Nelson tells him that he is the most important, as he is the main source of transportation. Alfie asks Oliver, who tells him that digging the foundation is the most important. Whilst Ned explains that their operators are the most important, as they are in charge of safety. Feeling confused, Jack and Alfie give up in their search.

However, when Thomas returns with his empty trucks, all the other machines are still in a commotion over it. Even Max and Monty decide to outdo each other by seeing who can collect the bigger load. Once loaded, Max and Monty speed out of the site, much to the concern of Kelly and Thomas. Racing each other side by side, Max and Monty are still arguing until they realise that Patrick is coming towards them. Patrick veers off the road, flies off the edge and accidentally falls into his own wet concrete, and splatters Thomas.

Miss Jenny hears about the news and scolds Max and Monty for causing a lot of trouble, especially since Thomas is covered in concrete. Max and Monty explain about the commotion, only for Miss Jenny to explain that, as they are all part of a team, there is no such thing as "Most Important". When Jack mentions Patrick, Miss Jenny scolds him for bragging about concrete.




  • Pre-filmed alternate footage from The Tortoise and the Hare is used.
  • The working title for this episode was "Who's the Boss?"
  • This episode marks the first appearance of Monty and Nelson.
  • This marks Byron's first speaking since the sixth series episode, Jack Jumps In.
  • This episode marks the only appearances of Patrick and the Community Centre Construction Site.
  • Virgin TV Anywhere's website refers to this episode with the title of the cancelled episode The Importance of Being Patrick.
  • In a behind-the-scenes photo, Patrick had his face removed in the scene where he fell into his concrete, as well as he was attached to some strings.


  • Jack's bucket bumps into the truck when he loads it.
  • When Thomas says "Makes my boiler ache!" studio equipment can be seen reflected in his pupils.
  • When Thomas leaves the foundations, his trucks disappear.
  • When Patrick crashes into the concrete, his undercarriage fan is visible and something blue in his cab (possibly his eye mechanism) is seen bouncing up and down.
  • Some of the concrete Patrick dives into splashes onto Thomas, even though the concrete was not initially shown to fly in Thomas’ direction at all.
  • Because some of the pre-filmed footage is used, the road appears to be sandy rather than being a normal paved road. Max and Monty have also swapped positions because of this.
  • When Max and Monty are about to crash into Patrick, Max's eyes are wonky.
  • The sky backdrop is visible in the top-left corner when the narrator says; "Patrick was pouring concrete for a new platform".
  • The position of Jack's bucket changes between the shots of him and Alfie reversing from the trucks and him saying; "Roasting radiators, it's hot".

In Other Languages

Language Title
Dutch Bouwen met Thomas
German Mit Thomas auf der Baustelle

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