Thomas takes the Fat Controller to see the site for the new school the Pack are preparing. After the Fat Controller leaves, Max tells Oliver to hurry up, but he takes no notice. However, his bucket hits something hard buried in the ground. Oliver's operator suggests that it could be important, so the Foreman calls Miss Jenny, who calls the Fat Controller, who calls the Experts. The Experts realise that Oliver has discovered a dinosaur bone. Using his chisel, Oliver digs away more earth to uncover a complete dinosaur skeleton. A photographer takes a picture of Oliver with the dinosaur and the following day, Thomas brings the Fat Controller, who shows the Pack that Oliver is on the front page of the Sodor Times with the headline: "Digger Digs Dino!"
Thomas takes Jack and Alfie to a warehouse site for work. The Pack are told to work carefully, or anyone who causes an accident will be sent back to the yards. Ned is worried since he always causes accidents, but he does not want to be sent back to the yards. His banksman tells him not to worry as he will watch over him. Everyone is working very carefully except Jack, who is not quite as careful as he is going too fast. Kelly tells Jack to slow down but Jack thinks he will be fine. However, he backs up and knocks over part of a stack of roofing slate, but no one, not even his banksman notices. Jack knows what he just did, but he does not want to go back to the yards, so he fills his bucket with gravel and drives away. Ned comes over and accidentally drives over the slate. His banksman blames him for knocking them over, but Ned corrects him that he did not do it. Unfortunately, no one believes him, so regardless of what he just said, his banksman calls Miss Jenny. As Ned is about to be sent away, Jack sees Ned heading to Thomas' well wagon as Alfie pulls up alongside. Alfie tells Jack about what Ned had "done" and that Thomas is taking him back to the yards. Alfie asks Jack what is wrong, but Jack has no time to answer him, so knowing that it was all his fault, Jack admits to Miss Jenny the truth that he knocked over the slates, which makes her briefly upset. Jack apologises to Ned for getting blamed and Thomas takes Jack back to the yard, proud of him for owning up.
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 falls into his own wet concrete. 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.
Percy has been sent to work with Alfie on Halloween night. During a break, Kelly decides to tell everyone a scary story about a one-eyed truck. Percy and Alfie hope that the story is not too scary. Max and Monty then complain that "it's just a story." Jack finds this insulting, so he shushes them. With that, Kelly begins to tell the story. Later, after teasing everyone about the story, Max and Monty are sent to dump some dirt. After seeing some things on their way, they see a light and thinking it is the one-eyed truck, run away in fright, but soon feel silly when they realise it was Thomas.
Kelly is blown over by strong winds while working at a site. He is repaired and returns the next day. Kelly is nervous about being blown over again, but when news comes that Isobella has come off the road and is teetering on a bridge, Kelly bravely goes to the rescue and regains his courage.
Byron is disappointed when his hard work is being ignored. When Max and Monty's reckless behaviour causes a water pump to burst and Alfie becomes trapped in thick mud, Byron rushes to the rescue and finally gets the attention he deserves.
Thomas is taking Jack and Alfie to the forest to stop a large old tree from falling after being struck by lightning. But as the machines make their way towards the tree, Max and Monty carelessly race around the forest and crash into the tree, causing it to start falling. Alfie, Oliver and Kelly hold the tree up while Jack goes to Thomas' flatbed truck for the props. He returns in time and the tree is saved.
Thomas and the Pack have been sent to the football field to clear debris from the car park after a bad storm, but there is no work for Buster and he feels left out. However, when the work is complete, Miss Jenny discovers mole hills on the field and sends Thomas to pick up Buster to flatten the mole hills, which he does successfully.
Nelson gets tired of his job of always having to carry the other machines to and from work and back home and he wishes that he could be carried for once. That night, Nelson has a dream that he is being carried, until Miss Jenny wakes him up next morning and informs him that Thomas had an accident at Maithwaite Crossing and Sir Topham Hatt needs Nelson to take him to the repair yard. Nelson arrives to see that Thomas had come off the rails and broken a wheel. Nelson is careful to load Thomas, but complains that he is "heavier than a bulldozer and a steamroller put together," much to Thomas' surprise as he is only a tank engine. While on their way to the repair yard, Thomas is impressed with Nelson and how nice it is to be carried for a change. Nelson tells Thomas he wants to be carried too, but does not think anyone is big enough to carry him. Nelson arrives on time where Sir Topham Hatt is waiting and he praises him for being a really useful lorry. Miss Jenny needs Nelson back at the yards, so Nelson says he would drive as fast as he can, but Sir Topham Hatt says that would not be necessary when Percy arrives to carry Nelson back to the yards, much to Nelson's delight. Nelson is loaded onto Percy's well wagon and is having a really splendid ride, which is as magical as he had dreamed.
Thomas takes Buster to the newly built Sodor Racetrack to smooth the track, but Max and Monty tease Buster about being slow and challenge him to a race. When the work is done, Miss Jenny allows Max, Monty, and Buster to test the racetrack. Max and Monty race off with Buster trundling behind, but Max and Monty end up in a ditch, while Buster trundles ahead and wins the race. When Thomas takes Buster home, Max and Monty argue over who came in second and third.
Thomas brings Ned to a demolition site; his friend is excited as he gets to demolish a building. However, Ned gets disappointed when he finds out that Oliver is given the task, and instead has to clear rubble. Oliver prepares to knock down a wall with a wrecking ball, but the wall does not collapse as it does not work. He is fitted with a larger one, but it does not work either. Meanwhile, Ned asks the foreman if he can help, but despite Oliver's attempts that keep failing, he declines by saying that it is Oliver's job. With that, Ned goes back to loading rubble, but he drops it onto the ground instead of the trucks because he is thinking about demolishing. Back at Oliver, they fit him with an even bigger wrecking ball, but still to no avail. Ned is still thinking about demolishing and does not pay attention. He collides with the chimney which collapses onto the building with the wall that Oliver could not demolish. While the workmen cheer, pieces of debris start falling onto and denting Oliver's roof, the corner of the destroyed building falls down, and Thomas is surprised to see his trucks being fully loaded. Ned is happy that he demolished the building, and asks Oliver if he wants him to demolish anything else. Oliver tells him that he thinks he has been doing enough for one day.
Alfie is upset when Max and Monty tease him about his size at a demolition site by calling him "small fry" and "half pint." Thomas tells him it does not matter as long as he is useful. Later, when Oliver is demolishing a building, Alfie hears a noise inside and goes to investigate. He finds a cat and her three kittens and rescues them before the wall collapses. The other members of the Pack cheer, even Max and Monty, and from then on, Alfie never complains about being small.
The Pack are digging foundations for the new dairy barn, but one by one they start to run out of fuel and become stuck. The lorry that was about to deliver the needed fuel breaks down, so Thomas is told to deliver the fuel to Isobella at Cronk. It is then up to Isobella to deliver the fuel to the site and get the rest of the Pack up and running.
